Anyone using the Halo Headset from Quiet Tech?

We have one report of a customer who experienced some VHF transmission issues when using a Halo headset from Quiet Technologies.     He apparently has narrowed down his VHF issues to the interaction between his IFD540 and this headset.  As soon as he goes back to his old Bose ANR headset, the problem goes away.

I definitely want to get to the bottom of this, so comancheguy do you talk regularly to ATC Center (Potomac Appr doesn't have an issue)?  This issue is seen almost exclusively with ATC center radios.  Other aircraft on freq or approach/regional controllers do not hear an issue.

The issue is described as a strong carrier with broken digital audio being transmitted with no static.

My pseudo-scientific hypothesis -- The ATC Centers use receivers with a much tighter band filter on them and somehow my halo headset causes a small freq shift from the selected frequency in the IFD540.  Again it's a hypothesis and I have really nothing to prove this.

I definitely would like to know if anyone else experienced this type of transmission issue headset or not. I have nothing more than a lot of trial and error and the issue seems with good certainty to follow the headset as I have now swapped them in flight.  I flew 40-50hrs trouble free hours with the old ANR headset.  My first flight swapping back with the QtHalo it returned upon contacting center and swapping headsets immediately fixed it.

I've got a lightspeed Zulu and my wife has a halo.  I've had left earcup issues on my Zulu that lightspeed has been trying to resolve.  Once in a while it puts out a very loud high pitched tone that doesn't go away even after recycling the unit.

Ken,

Thanks.  I have two pair of halos, mine is from December 2009 and one of the very first where the company switched microphone types to get a different impedance.  My wife's halo is a few years newer than.
I have a Va to Co trip next week where I'll try all three headsets.

Ryan

AviJake wrote: I'm told they offer 4 part numbers, both 'standard' and 'low gain' configurations.  Might be interesting to hear what variants you folks have too.

Avidyne's feedback:

That is interesting and not at all the result we were expecting.

The IFD has an software ALC that adjusts the gain to try and maintain a 70% modulation depth. The filter has a attack rate so sudden changes in input amplitude will result in modulation being above or below that 70%.

 There are limits on the gain adjustment but this would not clip the audio signal. The only time you would run into issues would be when the modulation exceeds 100% since the receiver would need to detect the phase reversal of the carrier.

One more data point:  I now have a "new" Halo (built within the last few months) as well as an "old" Halo (~5 years old).  Both headsets work fine with my IFD.