Typically once a day, in the late afternoon, my HRV has a bit of trouble. The control panel goes blank, flashing white every second or so, and sometimes beeping as well. It seems like it's trying to boot up but failing, as if there's not quite enough power or something, so it dies and then tries again. I try disconnecting and reconnecting the control panel from the wall but it doesn't help at first. I have to wait a couple of hours or so, and then reconnect it before it comes right again.

It kinda seems like a power issue. I've tried measuring the voltage coming from the cable and it shows 5V, so not sure what the issue is. The battery also seems good, though I guess that's only used for retaining the time?

Any advice would be appreciated. I really don't want to have to contact HRV. I'd be happy to replace the controller if I could be sure that would fix it.

[edit] It's a touchscreen, single fan system (plastic box), maybe 9 or 10 years old.