Hi all
Is anyone successfully playing 5.6MHz DSF files on a RPi2 with USB DAC?
I have the following setup:
WDMyCloud 4Gb NAS → 100 Mbit/s Ethernet → Raspberry Pi 2 Model B → USB 2.0 → Chord 2Qute DAC
Unfortunately the music cuts out for about one second every two or so minutes.
All lower resolution DSF and FLAC files play flawlessly.
Experimenting with ‘Audio buffer size’ and ‘Buffer before play’ settings make no difference.
I tried Volumio but it also suffers from the same problem.
Testing the ethernet using a 256MiB test file reveals 11.7 MB/s throughput which should be sufficient given 5.6MHz DSF play at 1.35 MB/s. All the same I copied the DSF files to a USB drive where I measured 22.5 MB/s read but the dropouts still occurred during playback.
All four CPUs on the Pi remain at less than 5%.
Stopping the nginx web server, samba and every other service I could get away with made no difference.
Verbose MPD logs aren’t reporting anything.
The only hint of something wrong that I can identify is the occasional CPU spike caused by by the ksoftirqd process when the dropout occurs. Could the USB bus be firing too many interrupts to be processed real(ish) time?
Am I hitting limitations of the RPis shared USB bus?
Does anyone have any pointers on how to diagnose further or able to confirm these problems don’t occur on a different device, say the Raspberry Pi 3 or one of the other supported devices?
RuneAudio version: release version: 0.4 (build: beta-20160313)
Debug info here - http://pastebin.com/031XitGW
Thanks for any assistance.
Calvin.
