I have a 55" Roku Select Series TV (Model 55R4A5R) that has a bug with the Live TV Pause Function for over-the-air antenna TV. With a USB stick installed and configured for this function, the video stutters, the audio looses sync, and/or the buffer gets cleared as it stores data on the USB stick. This issue has not been fixed for over a year as demonstrated by numerous posts on this web site.
I have tried several things to address this issue, including resetting the TV, using four different USB sticks, using different antennas, disconnecting everything from the TV except for the power cord and antenna, and disabling all picture processing and/or advanced networking features. Nothing has worked so far. I have tested this function on an older TCL 4 Series Roku TV with the exact same Roku Software (version 14.1.4 build 7709), and it does not exhibit this problem. The older TV always maxes out the full 90 minutes of buffering time, even with a weak antenna signal. The new TV has never gone more than 45 minutes without a glitch that clears the buffer, and usually fails within five or ten minutes even with a strong antenna signal. I even tried formatting several USB sticks with the older TV, and then used them on the new TV with no success.
I have worked with Roku support on this issue using a chat session (Ticket ID for Reference: 11592770). They could not provide a solution, and are escalating the case to the concerned department. Their Backend team will check and provide an update through email in 2 business days. Unfortunately, several other users on this site have gone through the same process over the past year, and have not met with any type of successful resolution.