Runeaudio downsampling via USB output?

[fongalv]

Hi guys, I'm back this time with an operational issue which I can't seem to fix/understand, and was hoping someone might have an insight to my problem.

My Rpi2 is currently streaming files(via USB wifi dongle) from a desktop harddisk, and the Rpi is feeding via USB to an SMSL m6 DAC which is identified by Runeaudio out of the box and selected in the MPD output settings. The m6 is spec'ed to receive 16-32bit signals via USB.

When Runaudio playbacks 16/44.1, this is reflected correctly on the DAC.

When Runaudio playbacks 24/192, the DAC shows 16/192.

When Runaudio playbacks DSD(DSDbit, 352.8khz), the DAC(which has no native DSD support) shows 16/352.8.

It currently seems as if the USB output is locked at 16bit? At boot, the DAC shows USB>32bit/352.8kHz, but the moment I pipe any music through, it changes to 16bit/xxxkHz. I'm unable to test spdif output until the digi board comesin, but that would be another week or 2.

Any ideas or suggestions what might be the cause?

[Aquarius]

What about the program doing the streaming on PC side? Is it possible that it ressamples before sending the audio stream to the Rpi?

[fongalv]

Hi, the PC harddisk was mounted directly within Runeaudio, so there should not be any streaming/conversion as far as I'm aware?

For the record, I've also tried playing the same files off a usb drive directly connected to the Rpi2, and the result is the same, so ruling out wifi issues between the rpi and pc as well.

[Aquarius]

Ah ok, I thought you were using DLNA or Airplay to stream from a PC to the Rpi. So no streaming, direct playback...
No idea then.

[fongalv]

Yea, I'm still doing some test to see if my dac is the issue(however unlikely since its only displaying what it's receiving via usb). Have a digi+ board coming in soon to see if it will make a difference(via coaxial). Either way, it still does not explain why usb does only 16bits...

[hondagx35]

[fongalv]

Hi Frank, what do you mean by "change card1 to your needs"? Sry, Linux noob here, but I will be able to test it once I'm home.

What card number are you referring to?

[hondagx35]

[hondagx35]

[fongalv]

Hi Frank,

Thanks for the detailed instructions, I know how to access the command prompt so that part is covered.

I have the digi card on order, currently still using direct USB-DAC output, what do I enter then?