Heavy CPU usage when compositing enabled and Audacious window open

Xubuntu 20.04, Xfwm4 4.14.2 (revision bb38fd90)
Xfw4 vblank = "auto" / GPU = Intel HD Graphics 4600

If the Audacious window is open and compositing is enabled the xfwm takes a large chunk of CPU compared to when compositing is disabled.