Hi Jaroslav,
I think I found it. I followed the spdif in and it leads to U19 which is an AKM AK4114VQ ("High Feature 192kHz 24bit Digital Audio Interface Transceiver"). It's the topmost of the very right of the card (below the "M-AUDIO" lettering).
There is code for this chip in the driver-source (i2c/other/ak4114.c) and it's also referenced in the code for the Audiophile 192 (see revo.c and revo.h).
Or do you think there's another chip involved?
- Jonas
2013/1/26 Jaroslav Kysela perex@perex.cz
I believe that there must be a S/PDIF receiver IC somewhere on the board and this IC may be wrongly configured. This IC is not handled in the current ALSA driver at all. Could you look to your board and check the used chips? From pictures on internet, a suspicious IC is in the middle of top on this PCI card. The AKM IC's are for analog audio outputs.
The ICE1724 chip has only serial SPDIF input and SPDIF input clock pins. The input samples should be copied to the DMA without any modifications (no volume control etc.).
Jaroslav-- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project; Red Hat, Inc.