[514077]

 

  Hey guys, little update regarding the popping and clicking issue.
 
AKM recently visited our China office and discussed the issue with us. The issue has been a noted issue regarding AK4490 DAC chip and AKM has asked Jason to help figure out a solution. The AK4490 DAC chip popping and clicking noises appeared at a lower frequency on the 600i and AKM is looking into the 600i to see what maybe causing the issues to appear at a lower frequency.
 
Questyle would like to thank those who have been affected by the popping and clicking issues for their patience in this matter. On the unit I have at home, I have at times heard the pops from time to time and am in the same boat waiting for a fix soon!
 
As this issue is related to the AK4490 DAC chip which is only found within the CMA600i, the CMA800i is NOT affected as it is using a Wolfson DAC chip.

I think the issue is with the USB controller, not the DAC itself.  The Schiit Modi 2 Uber, which I used full-time before I got the CMA600i, also uses the AK4490 and doesn't have the same issue.
 
The reason I say this is because the popping, at least as I observed it, would happen more often when I was doing something, like scrolling a web page.  My best guess is the drivers need to be better optimized.

As an outsider who loves reading Questyle threads, could it be, maybe, that your computer might need optimizing?  I only ask 'cause you said it happens when you're doing something such as scrolling.

 

[blinsc]

 
As an outsider who loves reading Questyle threads, could it be, maybe, that your computer might need optimizing?  I only ask 'cause you said it happens when you're doing something such as scrolling.

 
Do you own the CMA600i or have used it before?  I do, and here's what I know:
 
1) My computer is less than a year-old with an i7-6700K CPU, 16GB of RAM, and a GeForce 980 Ti video card.  I'm using the latest drivers for everything.  I don't have performance issues playing modern video games or with anything, really.
 
2) The Schiit Modi 2 Uber which uses the 4490 DAC doesn't have the same issue when using the USB input.  I've listened to it for hundreds of hours and never heard a single pop or click.
 
3) The CMA600i, which uses a different USB controller than the Modi 2 Uber, has issues 100% of time using the USB input, usually a couple times a minute (eg, about half a dozen times per song).  The problem can be exacerbated somewhat when actively doing something with the computer, like browsing web pages, which leads me to believe there might be some sloppy drivers.  If it happened with the Modi 2 (or any other devices I use) too then I would start looking at my computer.  But it doesn't.  Only the CMA600i and only using the USB input.
 
So people point the finger at my computer or the 4490 DAC but I don't believe it.  Since Questyle never got back to me in a meaningful way, I'm not anticipating a fix nor do I need one as I am using the coax digital input without problems.
 
Also, I don't care for your "could it be, maybe" question when all I am doing is providing information.  If you read the thread I'm not the only person experiencing issues with the USB input.
 
And to the person saying "it's not the USB input" and talking about clipping, that's not the same issue I am talking about.  I have not noticed any clipping issues.  What I am talking about are loud, audible "pops" and "clicks."  Like snapping your fingers together (maybe not that loud).
 
Unsubscribed.  Good luck any future buyers.

 

[DaveLT]

   
Do you own the CMA600i or have used it before?  I do, and here's what I know:
 
1) My computer is less than a year-old with an i7-6700K CPU, 16GB of RAM, and a GeForce 980 Ti video card.  I'm using the latest drivers for everything.  I don't have performance issues playing modern video games or with anything, really.
 
2) The Schiit Modi 2 Uber which uses the 4490 DAC doesn't have the same issue when using the USB input.  I've listened to it for hundreds of hours and never heard a single pop or click.
 
3) The CMA600i, which uses a different USB controller than the Modi 2 Uber, has issues 100% of time using the USB input, usually a couple times a minute (eg, about half a dozen times per song).  The problem can be exacerbated somewhat when actively doing something with the computer, like browsing web pages, which leads me to believe there might be some sloppy drivers.  If it happened with the Modi 2 (or any other devices I use) too then I would start looking at my computer.  But it doesn't.  Only the CMA600i and only using the USB input.
 
So people point the finger at my computer or the 4490 DAC but I don't believe it.  Since Questyle never got back to me in a meaningful way, I'm not anticipating a fix nor do I need one as I am using the coax digital input without problems.
 
Also, I don't care for your "could it be, maybe" question when all I am doing is providing information.  If you read the thread I'm not the only person experiencing issues with the USB input.
 
And to the person saying "it's not the USB input" and talking about clipping, that's not the same issue I am talking about.  I have not noticed any clipping issues.  What I am talking about are loud, audible "pops" and "clicks."  Like snapping your fingers together (maybe not that loud).
 
Unsubscribed.  Good luck any future buyers.

It's not the USB input.
 
Let's look at the evidence, I have a XD05 with XMOS AND AK4490. Any issues? Nope.
I even got questyle XMOS drivers to work on my XD05 and again, no issues.
Sloppy drivers? Yeah right. Stop talking out of your *beep*
 
You're just throwing a nail into a haystack and hoping someone finds it, it just doesn't make any bloody sense.
 
And since you don't know, here's the specs of my rig :
Intel Xeon E5 2675 V3
ASUS X99-A/USB3.1
FSP Aurum PT 1200
AMD R9 290X (AIO cooled)
Crucial Ballistix 32GB 2133

 

[514077]

 

   
Do you own the CMA600i or have used it before?  I do, and here's what I know:
 
1) My computer is less than a year-old with an i7-6700K CPU, 16GB of RAM, and a GeForce 980 Ti video card.  I'm using the latest drivers for everything.  I don't have performance issues playing modern video games or with anything, really.
 
2) The Schiit Modi 2 Uber which uses the 4490 DAC doesn't have the same issue when using the USB input.  I've listened to it for hundreds of hours and never heard a single pop or click.
 
3) The CMA600i, which uses a different USB controller than the Modi 2 Uber, has issues 100% of time using the USB input, usually a couple times a minute (eg, about half a dozen times per song).  The problem can be exacerbated somewhat when actively doing something with the computer, like browsing web pages, which leads me to believe there might be some sloppy drivers.  If it happened with the Modi 2 (or any other devices I use) too then I would start looking at my computer.  But it doesn't.  Only the CMA600i and only using the USB input.
 
So people point the finger at my computer or the 4490 DAC but I don't believe it.  Since Questyle never got back to me in a meaningful way, I'm not anticipating a fix nor do I need one as I am using the coax digital input without problems.
 
Also, I don't care for your "could it be, maybe" question when all I am doing is providing information.  If you read the thread I'm not the only person experiencing issues with the USB input.
 
And to the person saying "it's not the USB input" and talking about clipping, that's not the same issue I am talking about.  I have not noticed any clipping issues.  What I am talking about are loud, audible "pops" and "clicks."  Like snapping your fingers together (maybe not that loud).
 
Unsubscribed.  Good luck any future buyers.

It's not the USB input.
 
Let's look at the evidence, I have a XD05 with XMOS AND AK4490. Any issues? Nope.
I even got questyle XMOS drivers to work on my XD05 and again, no issues.
Sloppy drivers? Yeah right. Stop talking out of your *beep*
 
You're just throwing a nail into a haystack and hoping someone finds it, it just doesn't make any bloody sense.
 
And since you don't know, here's the specs of my rig :
Intel Xeon E5 2675 V3
ASUS X99-A/USB3.1
FSP Aurum PT 1200
AMD R9 290X (AIO cooled)
Crucial Ballistix 32GB 2133

You both are right.  I was only curious and didn't mean to stir anything up; especially when I don't know anything about either of your rigs.  Please don't unsub on my part.  I have no business commenting here, and will be gone from here.

 

[thatonenoob]

Cool so it's now time to start throwing out pc specs....sweet I'v got a...wait a sec...shucks. MBA

 

[simulatedrain]

I am not sure why you guys are arguing.  Two different questyle reps posted in this thread saying what the issue is.  So that confirms that yes there is indeed an issue running the cma600i through the usb, and hte company is looking at the ak4490 as the culprit.   Just because the same chips work in other devices without issues, doesnt mean it will work in others.  Questyle's implementation of the chips could be different, maybe theres issues with the drivers or some kind of interference.  No one really knows untill they find the problem and fix it.

 

[Staxaphone]

I read this thread while auditioning a 600i from my local Pittsburgh retailer.  I did not experience any pops or other such noises while listening to PCM rips from an HP notebook running windows 8 and VLC media player.  Output to the 600i was via USB with an AQ Jitterbug also attached to the computer USB port.  But needless to say I mentioned this thread issue to my dealer (Mark) when I visited the following day.  He immediately phoned "Bruce" (presume he is same Questyle person in this thread but I DO NOT know that for certain) and asked about this.  He said that he was informed by Bruce that the issue only occurs when switching between DSD and PCM tracks.  Anyway I bought the 600i and have not experienced a single pop or other noticeable noise artifact from the DAC.  I have yet to try any of my DSD iso rips ( I have over 150) as I listen to them only from my MB Pro through JRiver on my main system in another room.    

 

[up late]

the cma600i was driving the dynamic and planar magnetic cans that i auditioned today. i'm not sure which connection was being used tho. i expected it to be larger and was surprised by how compact it was. build quality looks nice and solid.

 

[allinhead]

do you know if it use 1 or 2 akm 4490 ?

 

[up late]

don't know

 

[heliosphann]

Another great review of the CMA-600i
 
http://www.tonepublications.com/review/the-questyle-cma600i-headphone-ampdac/

 

[MR. Hmm]

  I read this thread while auditioning a 600i from my local Pittsburgh retailer.  I did not experience any pops or other such noises while listening to PCM rips from an HP notebook running windows 8 and VLC media player.  Output to the 600i was via USB with an AQ Jitterbug also attached to the computer USB port.  But needless to say I mentioned this thread issue to my dealer (Mark) when I visited the following day.  He immediately phoned "Bruce" (presume he is same Questyle person in this thread but I DO NOT know that for certain) and asked about this.  He said that he was informed by Bruce that the issue only occurs when switching between DSD and PCM tracks.  Anyway I bought the 600i and have not experienced a single pop or other noticeable noise artifact from the DAC.  I have yet to try any of my DSD iso rips ( I have over 150) as I listen to them only from my MB Pro through JRiver on my main system in another room.    

It would be great if someone from Questyle could confirm/refute if this is the case. I want to buy the 600i but am hesitant because of the USB issue, but since I don't own any DSD tracks it wouldn't be a big problem as long as the issues are limited to switching between DSD/PCM.

 

[simulatedrain]

@MR. Hmm
 
Hey, i have the 600i and have personally experienced the pops and clicks.  For my situation at least, its not limited to just switching between  pcm and dsd.  It just happens in general if you use usb as source.  I can listen using optical with no issues.  Two representatives have said in this thread already that the issue is with the 4490 dac chip and that they are trying to solve the issue.  The pops and clicks during pcm to dsd changing is not something ive experienced, or heard of before.
 
USB issue aside if you can use another input source. i couldnt recommend this amp/dac enough.  It has a great design and is definately well made.    Has amazing functionality with various input and output combinations.  It has a very clean neutral sound that lets you hear your headphones characteristics.  Theres a few small legitimate gripes: volumn nob indicator is hard to see, and the controller has very few uses with the cma600i.  
 
@heliosphann
 
 
Another good read, im surprised we dont see more about this amp with how well received it seems to be at shows.  Would love to hear more about this thing powering the he-6.  Im interested in hearing how it sounds but having to acquire a special amp just for the headphones was a turn off.  Does anyone else have experience with the he-6 + cma600i?

 

[MR. Hmm]

Wonder how they will fix the problem with the USB. Is it likely that the units will have to go back to Questyle or can it be done with a firmware update or something?

 

[walfredo]

Hi Folks!!
 
Just got a Questyle 600i from another head-fier.  I am very please with what I hear!!  
 
Just curious about the remote.  It seems that only thing it does is raise/lower volume.  Do I need to do something for the other functions to work?
 
Thanks,
Walfredo