I'm having a lot of trouble putting my iPod Touch into DFU mode?

OK so i have had an ipod touch for a while and last year i jailbroke it. It went into safety mode, and i panicked and instead of just restoring it, i updated it, thus making it impossible to jailbreak from jailbreakme. I have tried multiple times with different softwares, and it just dosnt go into dfu. I got an iphone 2 weeks ago and out of curiosity, i tried putting that into dfu mode and it worked. 1st try. i think there is something wrong with my ipod, but everythinh else functions perfectly. i have tried to put it into dfu so many times and ik im doing it rite. is there anyway to jailbreak w.o dfu? why is this even hapening? please help!!!