[RipT]

OK, it didn't take as long as thought to get it running in a new user. I couldn't get it to crash until I enabled software filters and set it to "deinterlace" (yadif) for the de-interlacing method. Since it doesn't always happen in exactly the same spot, this could be a false correlation (in fact I couldn't reproduce it this time with the verbose debug logging activated), but I did get it to crash with the "deinterlace" setting, and nothing else activated (including no PVR). I notice there is a stack trace in the crashlog, so there's something wonky about the other user I was in before. Here's the new crashlog:

http://paste.ubuntu.com/6947597/

I'll keep trying to get it to crash with the verbose logging. Please let me know if you see anything in here that gives a clue to this.
Thanks again.