I use a similar setup but on GB band – not seeing anything like that but background RF is part & parcel of the world we live in:(
I see your two mics are (obviously) tuned differently but suggest retuning a bit to see if you can find a clearer patch and subsequent harmonic?
What are your squelch settings?
You have a lot of metal there, have you tried it with the antennae directly on the back of the receivers or everything separately out of the rack to see if that makes a difference?
In practical use once your mics are switched on this won’t be an issue – I never leave any radio receiver unmuted or slider up if it’s linked TX isn’t switched on.
E band here in the UK can get hit by bursts from mobile phone towers. This caused a bit of mayhem during a funeral at a local church. They didn’t have anyone doing sound and often left their faders up all the time. They don’t do that anymore 😉!
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