We use both AudioTechnica and Shure wireless microphones and have never had this problem. Typically when a battery runs out the mic simply stops working. One second it’s on, the next it’s off. We usually change batteries after 4 hours of shooting but I suspect we could get more out of them if we wanted to take the risk.
It sounds like perhaps there’s something else going on with your mics to cause the interference. Contact Azden tech support and see if they have any suggestions.
Jack
