I have 2 Roku Ultras, and I've been having problems playing video files off of my PC since around the end of October. I have plenty of bandwidth, I've checked with my Roku's both hard wired and wireless. I've tried both MYMEDIA and the Roku Media Player. My video's will start, and play briefly, before freezing up. I've tried several formats including the ones on the Roku list. Seems to be a buffering issue as before it locks up, it will start skipping like it doesn't have enough speed or buffer to pull from. I've been playing these files on Roku's for years. Any help would be appreciated.