I have several problems trying to play files higher than 48000 KHz and with bit depth of 24 bits. I submitted this to the users and got a resounding silence.
First- sample rate
Even though the documents claim that it will play at 176.4 KHz and 192KHz whenever I play a file at these rates it down converts to ½ the rate (88200 and 96000). I tested this with the ICE1724HT (Juli@) which has almost the same core, I never could get 176.4KHz at the SPDIF output. I confirmed that the ICE1724 will play the file at 176.4KHz in Windows so its not a hardware limitation. I tried to do the same with the VT1708 (on a Via CX700 chipset) and the Windows driver wouldnt let me at anything other than 48000.
Second, the only way I can get the 24 bit files out in a form that the card can play is to pass them through dmix. But I need to reconfigure dmix for each sample rate. And Im not convinced that it isnt resampling twice, both at the input and the output. Or how to configure the buffers etc. to prevent underruns even when the only conversion is to pass a 24 bit file to the card.
Im trying to build a high quality music server that will pass the files to either the internal or an external DAC at the bit depth and sample rate they were recorded at. I have tried to understand the various plugs and settings but it seems they are all focused on mixing various streams. I want to send the files unmixed to the output. I cant figure out what set of plugs and settings in asound.conf would enable this.