Same here. I thought my antenna was busted but with all the LiveTv Pause issues I decided to try pulling out the USB stick and my channels came back. I've gone through 4 USB sticks already. They all work great for a couple months then it starts getting buggy before completely failing.
The jump-ahead issue described in the last post, I noticed that only happens when I rewind all the way to beginning of the cache. If i stop about 1 minute before it reaches the beginning (so like 89 minutes back) it won't bug out on me and I can catch up.
I love the feature, though and the USB sticks are cheap. Just hope Roku (or TCL in my case) will perfect this. Maybe upgrade the function, too?