I have 2 Roku-TV's (7201x), used at a business for displaying advertising videos via Roku Media Player. The systems updated on July 18th to 8.1.0 build 4139-38, now we cannot play any large video files, getting "An expected problem (but not server timeout or HTTP error) has been detected" error. I can play a 50k file, but any other video I have is 700k or larger and won't play. I've tried multiple flash drives, have reformatted the flash drive, performed a system reset, all with no luck. Is there ANY way to downgrade to test? Or is this a known issue?