NV3550 Noise

My NV3550 started making noise. It seems to happen only when clutch pedal is pressed put into any random gear the let off clutch then pressed again. Some times it can be stopped by putting in a different gear and letting off clutch a bit. Link is to video of noise. Any ideas if the trans is toast or maybe just a simple fluid change? Noise sometimes does not happen with clutch depressed in gear or neutral so not sure its the throwout bearing.

Got the trans out and there seems like a lot of shaft play. But the TOB seems to be dry too. Also has some grooves worn into it. Could the TOB be seizing up at times and rubbing against the groves it dug in?