I dont know if this has happend to anyone here but after a couple of years working fine the rear USB port on my WD TV Live (WDBAAP0000NBK-00) started acting up a few months ago.
At first I thought it was a problem with my DIR-655 router (by coincidence it was dropping wired and wireless connections left and right) or the DWA-131 wireless dongle I use to connect the WD TV but, after finally taking the time to solve this once and for all, tonight I have narrowed it down to the rear USB port.
This is what I tried:
1- Removed the DWA-131 USB dongle from my WD TV Live and connected it to my laptop (to discard problems with the USB dongle) opened up VLC and started streaming movies from my Synology DS212J, both SD and HD movies with no problems there, everything went smooth, picture and sound were all in sync and no hiccups
2- Removed the DWA-131 from the laptop, put it back in on the WD TV Live on the REAR USB port and problems begun… AGAIN, it could not stream the movie properly, I had to wait approximately a whole minute before I could even see the introduction play, not to mention that after a few seconds the stuttering begun all over again. I THEN decided to try it on the SIDE USB port… VOILA…!!! Working again. Not stuttering, no jumping, no waiting, no nothing… as good as the first day I hooked it up. Soooo… figuring that the REAR USB was toast I connected my 16 Gb Survivor thumb drive in the rear USB port and again it worked smoothly… HUH 
3- Hard wired the WD TV Live directly to the DIR-655 to root out router problems, network setup went smoothly and begun playing back another movie… smooooth as silk, its like the DS212J was directly connected to the WD TV… I even FF and RWD the movie without a glitch so everything is working correctly.
All this leads me to conclude the rear USB connector on the WD TV has gone on a wireless strike and will refuse to play anything media related after almost 2 years working properly; oddly it will work with a USB thumb drive WTH
One thing I noticed is that the DWA-131 dongle does get VERY HOT after streaming content, could it be that the heat generated somehow fried something on the inside of the WD TV, but again that would not explain why it is able to reproduce media playing from a thumbdrive.
Just my 0.02 cents.
