It happens when I'm playing a DVD. After around 20 minutes, the entire system does one of the two things:
Locks up, the sound repeats itself, and I have to reboot
Or
I lose X, logout, and doing even simple commands like ls result in a segfault.
The first error looks like the same thing that happens when your CPU gets really hot. My CPU (an Athlon XP 2000+ with the Palomino core), although it gets hot easily, is at a reasonable temperature (125-135F) when these lockups occur. However, it seems that MPlayer sometimes misdetects my CPU speed. Sometimes when I start the DVD, it detects my CPU frequency at random speeds, sometimes as high as 2200Mhz (I'm running my CPU at 1667Mhz, my board is sensitive to OCing). Even when MPlayer correctly detects my CPU speed, however, it still freezes. I have tried compiling MPlayer with the CPU runtime detection option, and still no improvement. Any suggestions?

PS: It happens with MEncoder as well.

did you compile mplayer from source? if so you may have specified run-time detection of cpu on /configure or it may have detected something else wrong like sse2 instructions on the athlon (doubt it) or if you dowloaded a package make sure it is architecture independant or specific to your cpu.

Hmm, I seem to have MMX2 enabled when I don't have it. I'll try recompiling without it, thanks.

Oops, turns out I did have MMX2 support, and disabling it didn't help. Any other suggestions?

1. bump

2. I have found out that running as root doesn't help, but running without X makes the program encode more video then it did (but it still freezes). I also tried disabling DMA on the drives, no change. Anyone?

have you tried encoding/playing different vieo's in different formats? it migth be the file, the codec, or something else, if it happens for avi, matroska and ogm w/ different video/audio codecs it is likely mplayer or a hardware error, otherwise if it only happens for one container/codec combo it could be the software used for that.

I do not think 125 degrees F to 145 degrees F is reasonable. Those temperatures are very hot for that processor. If you try a dozen active heatsink brands and models, then it is time to invest in water cooling. You may want to use compress air to dust the whole entire computer. If you do not want to invest in water cooling, you can use a house fan.

It's 125F to 135F, not 45. Also, I think the temperature is okay, because I can play games like Far Cry and compile my kernel and the thing is quite stable. I think I'll try the compressed air, though. I put my computer under my desk, which is a bit of a tight fit, so I'll look into that.

exodist: I'll try some AVIs and OGMs, thanks.

A little update:
AVIs and RMs play fine without problems (they're a little skippy, but that's due to them being on another HDD). I tried recompiling MPlayer with making it use libdvdcss/dvdread instead of mpdvdkit, but there's no change. Any other ideas?

no, but if you find a quiet compressor or something liek ti for a compressed air cooling system let me know, I use a p4 and those are generally cooler than athlons, but my harddrives get extreamely hot and I put them each in 5 1/4 drive bays with a drive bay empty between each (4 120gb's) and this is in a seperate case with nothing else in it to and I still can't touch them until the computer has been off a while :-( I have a lot of anime (legal fansubs) stored on them that I would hate to lose.

Oh, mine aren't that hot, one 60GB (my main), and an 8GB one for my music. It doesn't get very hot, but I've had data corruption/speed troubles with it before.

lol, 50gb of music here (legal for those who are concerned ;-)) but yeah heat is a problem for these faster/larger drives. I built a 3 node cluster, not to share cpu cycles, but to distribute the heat of all my peripherals.

You're one of those 'iPod' people, aren't you? .
Anyway, I think I'll recompile MPlayer with debug options and get some kind of debug info, maybe submit it. Thanks anyway to all!

no, ipods are to expensive and don't hold enough. But out of need for some kind of player I have an mp3-cd playwer in my car, I can burn a cd full of mp3's and play it no problem.

First - Don't run mplayer as root.

Second - If the whole system freezes, that probably means it isn't mplayers fault. Mplayer would crash. So the problem is something that is talking to your kernel. So I would bet on some module or driver that isn't working well. Try the differant driver options that mplayer allows to get a short term solution, for a definite solution you should try and find the source of the instability.

I once had a problem with large downloads and it turned out to be a bug in iptables when using one of the rules.