TiVo Mini needs to be unplugged and plugged in again to reset

for about the last six months, our Tivo Mini, connected to a Roamio, seems to lose connection quite often, solved only by unplugging and plugging in again. The TiVo and Live TV buttons get locked out and nothing will either wake up the Roamio, or the Mini. I can't be sure where the problem is.
All my TiVo units (Roamio, Mini, Premiere and TiVo HD) were previously getting IP addresses via DHCP. I've changed that today, and given them all static addresses. If this fails, does anyone have...

TiVo Mini needs to be unplugged and plugged in again to reset

TiVo Mini needs to be unplugged and plugged in again to reset