Anyone using the iPhone and Phonak's DuoPhone App?

I have issues with my Smart S HA’s losing signal in DuoPhone program whereby i don’t hear the same thing at the same moment, a delay in signal processing.
I happens in voice mail but mostly when on a call. If i move the phone around my ear to sometimes see if i can get better voice amplification, the signal between HA’s gets out of sync temporarily. Somehow there is interference. The DuoPhone Works fine in speaker mode.

I have a iPhone 3g and i tested it also on a iPhone 4, same issues. But yesterday i tested a friends new old-tech flip-phone with no issues. Audie and I were ready to send the HA’s back.