Hi,
scenario: rPi, diynhk xmos usb, dac sellarz 9018
external DIYNHK power supply +5 to GPIO pins 6 of rPI and+15 to dac
xmos feeded by usb, maybe tomorrw I'll connect external +5
NAS music collection mounted with NFS
symptoms: random glitch,crackles (I called farts) during play
never had this problem with alix board connected to exactly same xmos and dac
this evening I've found this kernel messages
[270402.735305] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
[270402.742730] smsc95xx 1-1.1:1.0: eth0: kevent 2 may have been dropped
[270404.108208] SLAB: Unable to allocate memory on node 0 (gfp=0x20)
[270404.108242] cache: size-32, object size: 32, order: 0
[270404.108355] node 0: slabs: 457/457, objs: 51641/51641, free: 0
[270404.108380] ERROR::_complete:357: dwc_otg_hcd: complete: cannot allocate URB TQ entry
I suspect the cause was eth usb sharing bus
cheers