Good (and some bad) news :)
Last two (or even three) weeks I was working on improving sound driver. Now it works with correct sample rate (48khz), it plays sound first time (there was issue that first aplay produced no sound, it was bug in uda1380-driver, I've fixed it and sent fix upstream, it will be merged into 2.6.30 kernel). But there's some issues with codec power management.
I managed to disable/enable codec power, but now suspend issues appeared (no sound after resume). Here's some details:
We had one big problem: we need to disable codec power when sound is not used (it saves ~20-30 mA of battery consumption), but unfortunately, after powerup/powerdown/powerup sequence CPU was not able to communicate with codec over i2c. I've fixed it in i2c-s3c2410 driver (i2c clock need to be disabled if there's no i2c transfer around). But there's major issue: after resume there's no sound. I suspect it's something about i2s clock, I'm checking... :)
Btw, I'm very close to get basic rx1950 hardware working reliable and stable :)
Patches will be available on download site, but no precompiled kernel.
Stay tuned for latest news! :)