Dr. Cathy Kurth, director of the Audiology & Hearing Aid Center in Scottsdale, is installing hearing aids that cancel feedback on cell phones.

Many hearing aids are not compatible with cell phones because the hearing aids attract background noise, feedback and whistling.

This is because digital cell phone conversations are transmitted over a wireless network using radio waves, which creates an electromagnetic field around the phone's antenna. This pulsating energy is picked up by a hearing aid's microphone.

The newest hearing aids feature multi-channel signals that process incoming sounds more clearly and cancel feedback.

"I have fitted hundreds of hearing aids with the newest technology," said Kurth. "People love the latest hearing aids for their cleaner, natural sound and the reduction in background noise."