Been happening for a few days. I'd hoped updating to the latest VLC would fix it.
Now using fully updated LXDE. I have a machine that grabs podcasts with gpodder and plays them using VLC which is outputting to pulse. Playing fine for 5 to 15 minutes and then the sound stops, the mouse crawls and (virtual) memory usage by the VLC process goes past 1GB size within a few seconds! If I don't catch it quick enough and kill VLC, the whole system gets baked forcing a reboot. If the leak is caught early, I can restart VLC and replay a file until it happens again.
Haven't tried yet any other combinations of hardware/software, except if I play the podcast files in XMMS there is no problem. Xmms is using the OSS driver which pulse, of course, emulates. So I don't yet know if it is pulse or vlc.
Sorry for the vagueness, just putting this out there in case it's not just my system that is somehow baulked.
Kernel is 220.127.116.11-pclos6.bfs