I was playing the large cell arena map cellarena_lg or something like that with Goku. At the bottom of the rocks there is a little cave place that you can go into. I went into it all the way to the back and aimed out onto the ground in front of the cave. I attempted to fire a kamehameha out to the front of the cave but hit the ground in front of me instead. This caused the game and HL to completely close down on me and also caused my sound to get jacked up (when it repeats itself over and over again and won't stop). I had to end task hl.exe to get this annoying sound glitch to stop.