Given that other devices are affected and that not all installations of 1903 are affected I feel like the issue is probably on Microsoft's side. For what it's worth I appear to be running firmware version 4.11.0 and hardware version 1.04.
Given that other devices are affected and that not all installations of 1903 are affected I feel like the issue is probably on Microsoft's side. For what it's worth I appear to be running firmware version 4.11.0 and hardware version 1.04...
Yes that's the driver. My DX3 Pro uses the EXACT same driver by default and it works without pops and crackles.
I think the Khadas needs a firmware update to be compatible with Windows 1903 and up again.
Here is the S/PDIF input performance. You activate it by just hooking up a USB power supply to USB port. I used the little switcher Wesion sent me.
View attachment 16368
With USB input, Channel 2 had some spikes around 10 kHz which are now gone, resulting in nearly 2 dB improvement.
I just used a phone charger with USB cable. That way, there is no data and it will switch to S/PDIF.
Nothing wrong with the I/V stage, good engineering all around. About the schematics:
Know that we get some sound signal with head phones direct connected to KTB line outs, that said its not really designed as a head phone out put but a good quality normal voltage line output so we should use it as its intended is my opinion and connect it to preamps poweramps or head phone amps
A couple of reasons guessing why the 100 ohms R43/R50 sits there and never should be removed is it protects or isolate opamp against any weird or nasty cable reactive loads, also it protect opamp for a directly short should user by accident make a short to RCA terminal, any connected cable or head phones will work as antenna picking up unwanted RF noice bleeding into feedback loop of opamp where R43/50 up to a degree help isolate such problem.
Makes sence you safer to mod or remove R50/58/43/57 when building KTB into same enclosure as the speaker amp, but then again will suggest why not just lower 1k/22k resistors a bit for power amp input section, it should relative give the same and then you shure KTB stay within specs and do not start any unknown for user out of band nasty hidden oscilation.
People here could not tell difference between D50 and D50s whatsoever. So I doubt sabre hump is a big deal, it's more for peace of mindto be honest i do not care about volume control balanced out etc. the current version would have been bought by me, but i do not understand if the ess hump is listenable or is more of a spec that noone really hears... but i think i heard that it can be noticed...
Twisted Pear Buffalo Dac (built it around 2012)