Becker radio noise on different headsets

Hello all

I fly a permit (Annex II) aircraft with a Becker 8.33. I have three different headsets acquired over the past few years and seem to always have a “fuzz” sound of varying degrees, irrespective of the headset I am using:

1. Lightspeed Zulu – fuzz sound, even where on the ground, radio check comes back as 3/5 or 4/5. Distracting and constant fuzz sound when intercom switched on;
2. Mendelhsson HM40 headset – 5/5 on the ground, no issues. Get airborne and fuzz sound again, albeit less and manageable but there nonetheless compared to on the ground. If with another headset (Peltor or DC 13.4), RHS says my voice is faint;
3. DC 13.4 – 5/5 on the ground but hissing sound as well.

[Edit to add that I have checked that the squelch is OFF, but the sound is similar to the squelch]

I flew solo on Friday with the HM40 and had the DC plugged into the empty RHS and it was so so (I was on the ground when swapping headsets). I acknowledge that it is better to have the same brand/model headset as a pair. I flew on Saturday with a co-owner and we ended up using his pair of 15 year old Peltor’s and they were fine which reinforces the same brand/model argument.

I gave him a listen to the sound I was getting from the HM40’s and Zulu’s (there were headsets all over the cockpit) and he could not work it out other than to suggest that the technology in even the HM40 was probably too sophisticated for the aircraft which is fine to a point, but the Becker is only a few years old so not entirely buying that logic.

If solo, I have recently been using the HM40 which works best (and was cheapest?!) but I am irritated by the fact that I cannot get the benefit of the Zulu – which works fine otherwise in other aircraft, e.g. Super Decathlon.

Before I start getting rid of one or another headset and getting a matching second one, I am trying to work out whether the problem is the headsets (likely but why is it the same issue for different brands/models on mine but not someone elses), something to do with shielding on the Becker (possible), a combination of the two (probable) or something else (probable – anything is possible, including me hearing a fuzz sound in my own head but thankfully, other owner confirmed I am not insane).

Any thoughts before I go deaf from the fuzz sound/hissing? Thanks in advance…!