Andy Burns wrote:
Jeff Layman wrote:

It's two single receivers.

I'd look at what is near(er) to the one that's been unresponsive that
might interfere with it, can't see the transmitter getting different
interference depending which ID it's sending.

There's quite a bit of stuff on 433MHz these days - car keys, garage door
openers, tank monitors, remote controls for lots of things... the
modulation seems quite basic and I wouldn't be surprised if it gets trampled
on by some other device on the band.

Theo