We added the DS-2CD2387G2P-LSU/SL(4mm)(C)/O-STD/BLACK and I’m trying to figure out if adding a power supply is required to access all the functions this camera offers.
When I play back footage it does’t play the audio.
There's a setting in the camera to choose between using the built in microphone or the line in input for an external mic. Depending on how you're recording the camera, there's also likely a choice of it you want to record audio.