A few weeks ago, while passing through KC center, I was on 132.7. On both Garmins, this distinctive rythmic sound was in the background. It wasn’t center’s problem, but mine.
Went to Business Aviation in FSD (a SC) and our trouble shooting ruled out the Garmins. Ended up being the EMAX module. Am waiting for a replacement now. What was strange was that it wasn’t on any other freqency that I could tell. It also initially sounded like it might have been bleed over from a mag or alternator.
Just thought I would pass this info along.
David Schwietert 203 RF PFD/TKS/Emax/Skywatch/Stormscope