AB Pulse 4K Rev.2 Twin Tuner HDMI problems:

I've used VU+ receivers for years now (currently having the VU+ Duo 4KSE) but fed up with lack of support from Vu+ I purchased the AB Pulse 4K Rev.2 Twin Tuner receiver as a second and possibly replacement receiver for my VU+ Duo 4KSE as there isn't much else out there at the minute. I have since had massive problems with anything using HDMI nearby whenever I use the Pulse receiver HDMI ARC seems to fair the worst. The only solution being switching off the AB Pulse from the rear. I have been doing the "satellite thing" for over 20 years and this is a first for me. Have done all the suggested things ie. upgrading cables etc. without success help needed please.