[brandnewgame]

Hello, I bought an iBasso D2 portable amp recently and I've been happy with it (apart from having to resolder one of the PCB headphone sockets as the jack was loose). All of a sudden the sound will only come out of one channel when connected via USB, while it's in stereo when connected via the line in. Since USB is digital my guess is that the whole data would be coming through, or none at all (as in, there isn't a unique pin for the channel which has stopped working, all the pins together make up a single stream of data). Please correct me if I'm wrong..

The problem is, I can't see a weak link in the connection from USB to the output socket.. in fact there's so many locations of solder that I can't figure out the route and all I can do is examine each one for a missing link. Perhaps it's the Burr Brown PCM2706 or the WM8740 that's the problem, not to mention the countless other parts i don't know the names of.

In other words.. HELP MEEE

 

[Nocturnal310]

Try changing the USB cable itself.

 

[brandnewgame]

Quote:

Originally Posted by Nocturnal310 /img/forum/go_quote.gif Try changing the USB cable itself.

Tried with different cables, computers, headphones.. I wonder what iBasso charges for repair. It's a waste to send it to Hong Kong and back for repair (if that's even possible), but it's also a waste to build a whole new one and send it

 

[brandnewgame]

I've just realised that sound is coming out of the 'missing' channel, but very quietly. Turning the volume knob still affects the volume, so it would seem (only a guess) that some form of amplification of the signal after the DAC stage is not being applied to this channel and it's independent of whatever controls the volume (I don't know if it's just the knob which does that).

I tested to see if the quiet output is from the other working channel (i.e. just one channel being played) and the behaviour is quite odd. Sound coming through the working channel will come out of an earphone at normal volume, but out of the other one quieter. Sound aiming for the broken channel will only come out of that earphone, very quietly. Therefore, there are still two (strange) channels..

Anyone know what component(s) might be used for bringing the level up so I can find it/them on the PCB? Also anyone know what the h is going on?

Thanks for reading

 

[odigg]

Quote:

Originally Posted by brandnewgame /img/forum/go_quote.gif I've just realised that sound is coming out of the 'missing' channel, but very quietly. Turning the volume knob still affects the volume, so it would seem (only a guess) that some form of amplification of the signal after the DAC stage is not being applied to this channel and it's independent of whatever controls the volume (I don't know if it's just the knob which does that).

I assume that the iBasso D2 has the same amping section for both the USB and stereo line in. If it working for the stereo line in then my guess it that something is funky with the DAC section or between the DAC and amplification section. The amp section seems to be working fine.

Do you have a way to test if the left and right analogue outs from the wolfson DAC are working properly? If you can do that you will know if the problem is after or with the DAC section.

 

[psyllium]

I reckon it might be the port sensor on the line input socket. I had the same problem with my Total Bithead. Plugging in/unplugging a line input a few times fixes the problem temporarily.

 

[brandnewgame]

Quote:

Originally Posted by psyllium /img/forum/go_quote.gif I reckon it might be the port sensor on the line input socket. I had the same problem with my Total Bithead. Plugging in/unplugging a line input a few times fixes the problem temporarily.

I think you're right

, when I half plug in an input jack it works over the USB, so I think I'll replace the input jack to ensure all the connections are soldered. Thanks, I would never have guessed that..

 

[brandnewgame]

Quote:

Originally Posted by odigg /img/forum/go_quote.gif I assume that the iBasso D2 has the same amping section for both the USB and stereo line in. If it working for the stereo line in then my guess it that something is funky with the DAC section or between the DAC and amplification section. The amp section seems to be working fine. Do you have a way to test if the left and right analogue outs from the wolfson DAC are working properly? If you can do that you will know if the problem is after or with the DAC section.

Thanks for your help too