To mute video detection on an active tab, right-click on Ant Video downloader icon and select menu item Mute/unmute video detection on this tab:

When video detection on a tab is muted, AVD icon will change into disabled state on this tab:

By default, when mute video detection is turned on, all non-active videos (those that are not downloading, merging or converting) are removed for the tab. You can configure removal option by checking setting When I mute video detection for a tab, also clear all non-active videos of it at Settings — Video detection — Detector page.

Note, that mute/unmute video detection feature has nothing to do with mute of audio feature, provided by your web browser. Also, there is no list of muted tabs in AVD user interface.