I have noticed strange physical mute button (and light) behaviour so I don’t think it’s a fault. I also had different behaviour between Type 2020 and Type 2023 so that confused me further. If I do further testing of MUTE and LED I will stick with the earlier Type 2020 to try to find results consistent with yours.
I had another quick look at this yesterday. I can only replicate the Mute button ‘lock up’ when the MCL2AV is in L.OPT 2.5, not 1.5. I used the BL3500 rather than a TV, and I could not get the same result every time. I think sometimes the result varied according to what order I did the Option settings (BL3500 before MCL2AV or the other way around), and I also think the behaviour changed depending on the order in which I then activated the devices!
The IR sensors are so very sensitive – this makes it very difficult to cover/shield each sensor to simulate two rooms! I resorted to placing the MCL2AV and sensor under a thick duvet to avoid it receiving IR commands!
