Contour boxes keep freezing & needing reset

We've had the new Contour boxes (1 DVR & 3 small ones for bedrooms) for about a month. Almost every time it starts a scheduled recording, you can't change channels, use guide or anything. Box must be rest then it's fine. If main Contour freezes, other boxes don't work.

Then yesterday, with no recording, froze with 3 little dots...& nothing would respond.

Do we need a tech to come out, a booster possibly or is this a known issue????