Roku freezes every few minutes

I have the same problem, and it's driving me crazy. It will sometimes just go black every four or five minutes, for about 10 seconds, then when the picture comes back, it's very low resolution for a minute or two, before it gets back to normal... This doesn't seem to be happening on every channel, so far it's 380 & 775 that are doing it all the time.  I have a TCL Roku TV and remote with voice ability, which only works about half the time. And sometimes the remote becomes completely unresponsive, I'll scroll through hundreds of channels, find one I want, then when I click the OK button, it just bounces back to the previous channel!