Hi Wendy
Despite the 'All Tracks Are Equal' mention, some are more equal than others (now, where have I heard that line before? !)
To Mute part of a Utility Track, it's a little different:

Firstly, select the required Utility Track from the Mixer

1: Press the Audio Edit button

2: Select the Volume Automation function

3: Click along the blue line and then drag the nodes to change the volume as required.

Hope this helps.

Trev

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