When Recording Demo...

Draga

im trying to record some demos of me playing for my digital video class. but whenever i use the command, record [demoname], i drop/get kicked from the server like 10 seconds later. ive been playing maps for hours, then used that command and bam, gone. occasionally ns will just plain crash, but i dont think its from the recording. any suggestions?
PS this happens on a variety of servers, so i dont think its just server security.

Depot

Ensure no one is talking when you record, otherwise it will crash.