Nav IV Voice Instructions Distorting With Sena SHM5

[buncobooth]

I have just bought a Sena SHM5 to hook up to my Nav IV and use for a few other things. My version came with the updated SMH10 larger speakers with locking connector, but I am getting distortion at high volumes from the Nav IV during voice instructions. The standard non TTS voice is better, then the male TTS and female one is the worst. It sounds like the level coming from the Nav is too high so when I turn the SHM5 up so I can hear them over earplugs and wind noise they are distorting. I have tried a phone and mp3's/audio samples from the Nav but the voice instructions are much worse. I can turn the volume down on the Nav for the voice but it still starts to distort when turned up on the headset. Anybody else have this problem ? I have done some reading and I think it is an issue with the Zumo. I tried another demo unit and it was exactly the same.

 

[Schtum]

What kind of earplugs are you using? If it's solid foam ones, you might get better using filtered ones such as these Alpine ones.... http://www.ebay.co.uk/itm/Alpine-Motosafe-earplugs-motorcycle-motorbike-free-p-p-/330591473444

I find I can use a lower output volume and still hear the navigation instructions and phone calls with these.