This sucks, I just started having the same problem, for no apparent reason at all. I have no idea what could have triggered it. The alarm is crashing the whole sound system, I have to shut down and start back up again to get the sound working again. And I can reliably crash the sound system again by either having an alarm go off, or go into the alarm setup and change which sound it is playing once or twice and then it will keel.

This is one of at least a half dozen unexplained issues I am having with my N810 right now. I've only owned it for a few weeks. Over that time I've had it crash and lost all my data, had to reflash it (for another reason), had to reformat the internal memory (for another reason), half the software I wanted wouldn't even install, among many other things. And all I've been doing is just installing software from maemo.org. I haven't even been hacking around with Linux. I started off praising this machine as the best thing ever in the first week. Now I'm ready to toss it in the trash as a useless disfunctional hacker's toy and invest in a umpc instead.