button battery contacts - it slides in there
Oops my bad. It didn't click until I saw the second set of pictures.
button battery contacts - it slides in there
Erm thought just occurs to me.
You have tried replacing the battery in the remote?
If it's weak it may not be strong enough for the conditions.
Don't know if it helps but when my microwave is on it can sometimes interupt the wifi signal in the kitchen (but it's pretty weak in that room anyway).
Never heard of IR being affected by Microwave ovens before. The difference in frequencies is huge, several orders of magnitude difference.
Maybe the microwave lamp is run by PWM at 38khz or a resonant frequency of 38kHz and pushing some IR. Or the fan motor is somehow causing the bulb to resonate. Bit of a stretch though.
Rule things out by trying the 'microwave/radio next to each other combination' in different locations.
Combine microwave with radio in bedroom for example.