Audio track has no sound

Imported audio has no sound.
I’ve:
enabled sound on the top bar
enabled sound scrubbing
installed quicktime
tried various formats
tried previewing the clip via the library

So what gives? audio works fine on my windows 10 machine but my main windows 7 workstation has this issue.

The new Quicktime version is broken on Windows 10, uninstall it and install
7.7.6 or 7.7.7 instead.

https://support.apple.com/downloads/quicktime