I use Hark (https://github.com/otalk/hark), a simple wrapper around the WebAudio API, to attach to a sender's mic stream to monitor for volume changes.

When I do this, inbound audio tracks on a peer connection attached to an audio/video element have corrupted audio: missing sound, skipping, static -- basically so bad it's unintelligible. The audio is even corrupt on other inbound audio streams not related to the outbound audio, so I'm guessing this is a global audio processing issue.