Sennheiser PC37X randomly goes bad after disconnecting the cable ?
Greetings, Yesterday I was using my headset like normal with my macbook, just listening to music and on a call with people like usual, and the headset was perfectly fine. The stock wire that came with the headset is extremely long and yesterday it annoyed me very much that it kept getting tangled with itself, so I decided to see if the cable is replaceable. I pulled out the cable from the headset and saw the adapter, and looked online for a replacement. Upon plugging it back in, the audio sounded extremely muffled and washed out. Im not sure what I did wrong to make it mess up like that as I've always taken good care of it, ive had it for about 2 years and its always just been chilling on my desk, but anywho I thought the cable just went bad and ordered a replacement. The replacement came, and the issue is still persistant, so I am not sure what the issue is I've tried multiple different headsets and the issue is not with the port, and I also tried it with my windows laptop and...
Apr 23, 2024
I fear that this is a bug in the hardware that can not be fixed, an example of typical chinese development and testing skills (read none).
Of course I have sent two messages to service@xduoo.com and one through the official Amazon channel, on 20 Dec and 22. So far no one replied.
@JCruck: Sorry, but you are wrong. The filters are part of the DAC chip, and that chip doesn't even know where its input signal is coming from. It seems you got confused with the sample rate conversion, which indeed is only available on the digital input, not USB.
@ myself: Further examination of the problem now even more points to a serious firmware flaw. The unit behaves differently between USB and digital input SPDIF:
USB: PCM 1 and 3 are Short Delay Sharp, PCM 2 and 4 are Short Delay Slow. Changing from PCM 1 to 2 'Slow' is activated for less than half a second, then the unit activates SD Slow. The same happens when switching from PCM 4 to 1, 'Sharp' gets active for less than half a second.
SPDIF: SD sharp is active all the time, no matter what is selected. Here also other filters can be seen for a very short time after switching through PCM 1 to4.
SRC: I have to add this feature as it reveals another flaw. Playing back 44 kHz with SRC off, it seems the SRC is not off. The signal looks somewhat deformed on a sample-level. Maybe the SRC is then still on and not properly bypassed - I can't say what exactly is happening. It just looks awful on a DSO to see the impulse response with high-frequency distortion on it. This is immediately solved when using the SRC, so upsampling to 192 kHz as standard operational mode for listening to digital sources would be the way to go.
All of the above is 100% reproducable on my unit. As a technician it seems clear to me that such behavior can not be caused by simple manufacturing errors, like contact problems or defective chips. This looks like a firmware bug, and I would not be astonished if all ever produced units have the very same problem.
And now that I wasted all my time with this I stumbled over the proof of my theory, on a russian website which hosts lots of XD-05 measurements. They show the exact same (wrong) impulse responses for the filter types with PCM 1 to 4.
http://reference-audio-analyzer.pro/en/report/dac/xduoo-xd-05-pcm1-spdif.php http://reference-audio-analyzer.pro/en/report/dac/xduoo-xd-05-pcm2.php http://reference-audio-analyzer.pro/en/report/dac/xduoo-xd-05-pcm3.php http://reference-audio-analyzer.pro/en/report/dac/xduoo-xd-05-pcm4.php
Makes me wonder if Massdrop will show any responsibility and force xduoo to provide a firmware bugfix...