[Mython]

  I just got my Mojo and have the problem with the first half-second of a track is cut off.  It happens on a MacBook Pro with Vox and Tidal.  I haven't tried other apps yet.
 
Chord really needs to provide a firmware update to fix this.  I don't have this problem with any other DAC.

 

Mojo in common with Hugo has a mute function . This occurs when the usb changes sample rate or switches to dsd. This is to eliminating the huge bangs that some os creates. Losing half a second is better than losing your headphone drivers.... Rob

 

  The problem of muting the initial start is due to certain OS and apps - when the sample rate changes, the data in the buffers get sent out at the wrong rate. When you switch from DSD to PCM you then get a loud bang, or track played at the wrong rate for a period. Now this fault is in the app, its absolutely nothing to do with the DAC.
 
So to fix the apps problem, if the sample rate changes, I force a mute for 0.5 seconds, so that you do not hear these noises. On some apps, you can force a small silent period at the beginning and this solves the issue.
 
If I didn't do this I would have people complaining about bangs thumps and music being played at the wrong rate. Better silence than shots being fired off!  
 
Rob

 
Some applications allow to set a delay in milliseconds, to overcome this.
 
 
 

 
Also, I noticed clicking sound when scrolling my trackpad in Safari.  I dropped the sampling rate in the Audio/MIDI Setup and that corrected the problem.

 
Your computer will consume quite a lot of CPU resources if unnecessarily upsampling, by default.
 
 
 
 
 
 
 
 
 
What resolution music files are you playing?
 
 
.

 

[zam1]

Hello all,
Thanks to the well deserved rave reviews here on Head-Fi, I'm now a happy Mojo owner. As a bit of a worrier, I do have a question I hope someone can answer. I downloaded some DSD256, 128, and 64 files to see what the Mojo can do. I'm using iAudiogate and my iPhone 6+ with Silver Dragon USB cable. First, I'm experiencing alot of intermittency during playback. I'm asuming that's a buffering issue, and it's happening with all 3 file types. Besides that, the bitrate indicator light appears to my aging eyes to be decidedly light pink, not white as I thought it should be for DSD playback. I'm really wondering if it's white, but is picking up some internal reflections from the red volume ball or if it's really pink. Anyone have a similar experience? Should I expect that bitrate ball to be an obvious white? Thanks in advance for any insights! 

 

[tjw321]

  I just got my Mojo and have the problem with the first half-second of a track is cut off.  It happens on a MacBook Pro with iTunes, Tidal, Spotify, and Vox!!!
 
Chord really needs to provide a firmware update to fix this.  I don't have this problem with any other DAC.

Also, I noticed clicking sound when scrolling my trackpad in Safari.  I dropped the sampling rate in the Audio/MIDI Setup and that corrected the problem.

I have a Macbook and I generally use Vox. I don't get any cut-off at the beginning of a track. AFAIK I'm using default settings with everything, though I think I may have ticked the "Synchronize Sample Rate with player" box on the Audio tab of Vox.

 

[GRUMPYOLDGUY]

 I just got my Mojo and have the problem with the first half-second of a track is cut off.  It happens on a MacBook Pro with iTunes, Tidal, Spotify, and Vox!!!
 
Chord really needs to provide a firmware update to fix this.  I don't have this problem with any other DAC.

Also, I noticed clicking sound when scrolling my trackpad in Safari.  I dropped the sampling rate in the Audio/MIDI Setup and that corrected the problem.

I have a Macbook and I generally use Vox. I don't get any cut-off at the beginning of a track. AFAIK I'm using default settings with everything, though I think I may have ticked the "Synchronize Sample Rate with player" box on the Audio tab of Vox.

It might have to do with your laptop. Do you have the same issue with Tidal on your phone going through the Mojo?

I'm using an Xperia Z5c to Mojo via USB with the Tidal app and don't experience this problem.

Regardless, I don't know if a FW upgrade is possible without sending back to the factory. There is no external JTAG header and most people don't have a Xilinx programming pod and a licensed copy of Vivado anyway.

Sent from my E5803 using Tapatalk

 

[Mython]

  I downloaded some DSD256, 128, and 64 files to see what the Mojo can do. I'm using iAudiogate and my iPhone 6+ with Silver Dragon USB cable. First, I'm experiencing alot of intermittency during playback. I'm asuming that's a buffering issue, and it's happening with all 3 file types.

 
It may be a buffering issue or it may be your iPhone CPU is struggling to keep up - I've even seen Macbook Air and Macbook Pro users struggle to output DSD256 and DSD128 flawlessly. It's not a fault with Mojo (sincerely; it really isn't).
 
 

   the bitrate indicator light appears to my aging eyes to be decidedly light pink, not white as I thought it should be for DSD playback. I'm really wondering if it's white, but is picking up some internal reflections from the red volume ball or if it's really pink. Anyone have a similar experience? Should I expect that bitrate ball to be an obvious white? Thanks in advance for any insights! 

 
 

The reason the ball is not 100% 'white' is because there is no white LED in Mojo - the white is a composite colour from several other LED colours, so sometimes the combination isn't pristine white. It's absolutely nothing at all to worry about.
 
Here is what John Franks (the founder of Chord Electronics) said about this:
 

 

No it was definitely the pink colour of the 768khz sample rate, it sounds fantastic but it's just bugging me that it isn't showing or decoding the correct thing.

From JF the white colour is made up of three colours. These are shades of red green and blue from three seperate leds although we have done our very best to insure a pure white however without the precise colour balancing circuitry that TVs have. It is possible that sometimes due to an inbalance of brightness between the three LEDs there might be a slight colour shift towards one of them. If this is the red led there might be a slight pink tinge to the composite White of the three LEDs it's nothing to worry about.

 

[flargosa]

I just bought a new Mojo. After charging it for 12 hours straight and using it maybe 7 hrs after charging, I decided to do a burn-in on the Mojo.  It looks like the Mojo while charging cannot keep up with its power usage.  Is this normal guys? My Mojo runs out of battery while charging, and the battery LED is blinking red.  Is the Mojo’s charging speed less than my IEM’s power requirements?  Is this normal or should I return my Mojo for a replacement?  
 
 
My setup 2amp 10 watt Apple Charger >> Mojo >> SE846.  Source is iPhone. 

 

[Mython]

  I just bought a new Mojo. After charging it for 12 hours straight and using it maybe 7 hrs after charging, I decided to do a burn-in on the Mojo.  It looks like the Mojo while charging cannot keep up with its power usage.  Is this normal guys? My Mojo runs out of battery while charging, and the battery LED is blinking red.  Is the Mojo’s charging speed less than my IEM’s power requirements?  Is this normal or should I return my Mojo for a replacement?  
 
 
My setup 2amp 10 watt Apple Charger >> Mojo >> SE846.  Source is iPhone. 

 

 
Mojo, like Hugo, has been designed so that you can have the charger plugged in constantly. So on a desktop charge and run it at the same time. Once its fully charged, the charger will just supply enough current to balance Mojo's current draw, so no net current from the battery.
 
Rob

 
 
So, you charged it, then used it for 7 hours, and then connected it back to the charger and immediately started using it whilst charging?
 
 
It may depend on how low the battery was when you started using it again - if you'd been using it for 7 hours, previously, it may have been very near to flat. If that is the case, then the charging circuit will not allow much charging current to the battery, so it is possible that this restricted level of charging-current might not be enough to play and raise the battery charge. So, basically, it may have been a situation that falls in between the two scenarios, below:
 

  Just to clarify. Charging is automatic. If you are playing and charging at the same time, with a fully charged battery, the charger will supply enough current to balance the consumption used by Mojo, so no net current into the battery. If its fully charged and the unit is off, the charger will go off. The charger will re charge automatically when the battery voltage falls to 8.2v (off at 8.4v) so keeping the charger connected will ensure a full charge.
 
Rob 

 
 
So, if you hadn't already used your battery for 7 hours before you reconnected the charger, then the battery would probably have been easy to recharge, even though you were still playing music.
 
But, after 7 hrs of use, the battery was probably very nearly flat, so the charging circuit might have reduced the charging current, to some extent:
 

  Sounds like the battery is completely flat.
 
When this happens, the charger charges with a very small current, as Li batteries can't be charged with full current with a low battery voltage.
 
So try charging for several hours with the unit switched off. You need to keep the unit off during this period, as the charging current is not enough to both charge and keep the unit on.
 
Hope this works, Rob

  The charging circuit looks at the state of the battery before charging. If the battery has a very low voltage, it will trickle charge the battery until it gets to a safe voltage, and then full charge will commence. This trickle charge mode can take several hours, and it is done for safety reasons, and it will appear that the battery is not working as the trickle charge mode takes some time. When in this mode Mojo must be off.
 

 
 
That would be my guess, at this point, but I'm not stating it as 100% bulletproof explanation of your experience.

 

[GreenBow]

  I just bought a new Mojo. After charging it for 12 hours straight and using it maybe 7 hrs after charging, I decided to do a burn-in on the Mojo.  It looks like the Mojo while charging cannot keep up with its power usage.  Is this normal guys? My Mojo runs out of battery while charging, and the battery LED is blinking red.  Is the Mojo’s charging speed less than my IEM’s power requirements?  Is this normal or should I return my Mojo for a replacement?  
 
 
My setup 2amp 10 watt Apple Charger >> Mojo >> SE846.  Source is iPhone. 

 
If you play teh Mojo and charge it from flat, it will not reach full charge. It cuts off after about six hours. You have two choices.
 

1. Either switch off charging for a second and swithc it back on; every few hours.
2. Or as most of us do, fully charge the Mojo, and leave it plugged into power while playing. It runs cooler this way that trying to charge and play from flat.

 

[flargosa]

Ok thanks guys, I'll do a full charge before restarting my burn-in and see how it goes from there.

 

[zam1]

Thanks so much Mython! It now makes sense and puts my concern to rest that there might have been something wrong with my device. Really appreciate that you took the time to find that other post too!

 

[zam1]

   
It may be a buffering issue or it may be your iPhone CPU is struggling to keep up - I've even seen Macbook Air and Macbook Pro users struggle to output DSD256 and DSD128 flawlessly. It's not a fault with Mojo (sincerely; it really isn't).
 
 
 
 

The reason the ball is not 100% 'white' is because there is no white LED in Mojo - the white is a composite colour from several other LED colours, so sometimes the combination isn't pristine white. It's absolutely nothing at all to worry about.
 
Here is what John Franks (the founder of Chord Electronics) said about this:
 

Thanks so much Mython!

 

[Mython]

.
 
 

Spoiler: Warning: Spoiler!

 

  I just bought a new Mojo. After charging it for 12 hours straight and using it maybe 7 hrs after charging, I decided to do a burn-in on the Mojo.  It looks like the Mojo while charging cannot keep up with its power usage.  Is this normal guys? My Mojo runs out of battery while charging, and the battery LED is blinking red.  Is the Mojo’s charging speed less than my IEM’s power requirements?  Is this normal or should I return my Mojo for a replacement?  
 
 
My setup 2amp 10 watt Apple Charger >> Mojo >> SE846.  Source is iPhone. 

 

 
Mojo, like Hugo, has been designed so that you can have the charger plugged in constantly. So on a desktop charge and run it at the same time. Once its fully charged, the charger will just supply enough current to balance Mojo's current draw, so no net current from the battery.
 
Rob

 
 
So, you charged it, then used it for 7 hours, and then connected it back to the charger and immediately started using it whilst charging?
 
 
It may depend on how low the battery was when you started using it again - if you'd been using it for 7 hours, previously, it may have been very near to flat. If that is the case, then the charging circuit will not allow much charging current to the battery, so it is possible that this restricted level of charging-current might not be enough to play and raise the battery charge. So, basically, it may have been a situation that falls in between the two scenarios, below:
 

  Just to clarify. Charging is automatic. If you are playing and charging at the same time, with a fully charged battery, the charger will supply enough current to balance the consumption used by Mojo, so no net current into the battery. If its fully charged and the unit is off, the charger will go off. The charger will re charge automatically when the battery voltage falls to 8.2v (off at 8.4v) so keeping the charger connected will ensure a full charge.
 
Rob 

 
 
So, if you hadn't already used your battery for 7 hours before you reconnected the charger, then the battery would probably have been easy to recharge, even though you were still playing music.
 
But, after 7 hrs of use, the battery was probably very nearly flat, so the charging circuit might have reduced the charging current, to some extent:
 

  Sounds like the battery is completely flat.
 
When this happens, the charger charges with a very small current, as Li batteries can't be charged with full current with a low battery voltage.
 
So try charging for several hours with the unit switched off. You need to keep the unit off during this period, as the charging current is not enough to both charge and keep the unit on.
 
Hope this works, Rob

  The charging circuit looks at the state of the battery before charging. If the battery has a very low voltage, it will trickle charge the battery until it gets to a safe voltage, and then full charge will commence. This trickle charge mode can take several hours, and it is done for safety reasons, and it will appear that the battery is not working as the trickle charge mode takes some time. When in this mode Mojo must be off.
 

 
 
That would be my guess, at this point, but I'm not stating it as 100% bulletproof explanation of your experience.

 

 

 
If you play the Mojo and charge it from flat, it will not reach full charge. It cuts off after about six hours. You have two choices.
 

1. Either switch off charging for a second and switch it back on; every few hours.
2. Or as most of us do, fully charge the Mojo, and leave it plugged into power while playing. It runs cooler this way that trying to charge and play from flat.

 

 
 
 
Further to our collective replies, yesterday (which were on-target), I have since been told the following, directly from the horse's mouth, for the purposes of clarification:
 
 

   
The reason why you want it to go into fully charged mode before running fully into desktop mode is if its nearly flat, then the current to charge the battery is only a third of what it should be as Mojo is running - so it will take about 12 hours to charge. But 12 hours will mean the timer safety circuit may step in, in which case Mojo charger will need resetting by disconnecting the charger, then reconnecting the charger.
 
By running connecting it fully charged (or for that matter half charged) it will get to the trickle charge mode without fault; once in trickle charge mode, the battery will be permanently in blue, and the charger will supply enough current to match what Mojo needs - and the charger can supply trickle current for ever.

 
 
Cheers, all. Have a good Sunday!
 
                                                         

 

 

[GreenBow]

@Mython, yes I remember Rob saying that a while ago and it confirmed what I had found out. I discovered it way back in about early February 2016 when I finally opened my Mojo. Great of you to add Rob's explanation.
 
I wish someone could tell me what I need to do to achieve bit-perfect on a transport to feed the Mojo.
 
Do USB Player Pro, or Onkyo HF Player put out bit-perfect (anyone please). Can it be done across USB from a phone or tablet? (Sorry but I know nothing about phones or tablets.)

 

[glockhit]

Hello all,
Thanks to the well deserved rave reviews here on Head-Fi, I'm now a happy Mojo owner. As a bit of a worrier, I do have a question I hope someone can answer. I downloaded some DSD256, 128, and 64 files to see what the Mojo can do. I'm using iAudiogate and my iPhone 6+ with Silver Dragon USB cable. First, I'm experiencing alot of intermittency during playback. I'm asuming that's a buffering issue, and it's happening with all 3 file types. Besides that, the bitrate indicator light appears to my aging eyes to be decidedly light pink, not white as I thought it should be for DSD playback. I'm really wondering if it's white, but is picking up some internal reflections from the red volume ball or if it's really pink. Anyone have a similar experience? Should I expect that bitrate ball to be an obvious white? Thanks in advance for any insights! 

I am seeing the same thing when playing a DSD file the ball is pink not white. Also it shows the DSD file playing at 325800.0HZ. I haven't been able to get an answer on the ball lightning up pink. I do remember users of the Chord Hugo having problems with the light colors not being accurate.

 

[glockhit]

When I play a DSD music file on my mojo the frequency ball doesn’t light up white as shown on the mojo diagram. The light is a purple magenta color and in Audirvana it shows the song playing at 352800.0 hz. I’m not sure whats going on and why the frequency ball on the mojo isn’t showing “white” as a DSD file.


In Audirvana Plus I have it set on Native DSD capability “automatic detection”
DSD to PCM algorithm set to 64bit algorithm if applicable.

I am using a Macbook Pro 2015 with Audirvana Plus

My Macbook midi player shows a DSD file playing at (format 352800.0 Hz)

Appreciate any help. I searched and couldn't find anything to help me with this.

I posted this on another forum with no solution yet. Perhaps someone can help me here.