Playback is sped up and distorted.

[Tony1]

Playback is sped up and distorted when using the visualiser graphic In the right sidebar.

[hiccup]

Playback is sped up and distorted when using the visualiser graphic In the right sidebar.

Yeah, don't waste words or explain detailed circumstances.

You have found a giant bug. Nobody realized before that MusicBee sped up and distorted the sound.
Your post clears it all up, and thanks to your detailed report I am sure it will be solved very soon.

(please don't blame other members for not noticing this, it even took you a year to notice and report this)

[Steven]

Playback is sped up and distorted when using the visualiser graphic In the right sidebar.

If you are using a BassBox visualiser plugin with ASIO or WASAPI exclusive output then this is a known issue that has been reported serveral times which you would have discovered using the forum search.
There is no fix pending to address this but these should work: using WASAPI (shared) output or using a winamp or Windows media player visualiser (Alchamey i think).