Best Sellers in Audio Baby Monitors. #1. VTech Upgraded Audio Baby Monitor with Rechargeable Battery, Long Range, and Crystal-Clear Sound. 40,158. 8 offers from $16.85. #2. VTech DM221 Audio Baby Monitor with up to 1,000 ft of Range, Vibrating Sound-Alert, Talk Back Intercom & Night Light Loop, White/Silver. 32,943. 12 offers from $25.77.