Ok. It's a bit challenging to help because of the inconsistencies between what you've posted and what's actually happening. PD vs AD for one, and stating that you'd downloaded the clips from DirectorZone when they're actually from the PD365 Background Music library. Those are completely different sources.
Meanwhile, Crisp Afternoon has full volume and no distortion on my system in both PD365 and AD. Here's the PD audio waveform shown without any modifications:
As I wrote in my last post, it seems like something in your audio chain isn't set correctly and the that lines up with both AD and PD being affected. The DxDiag results show that you have 3 audio drivers installed, and the quickest way to figure out which one is giving you trouble is to right-click on the Windows taskbar Volume icon and choose Sound Settings. (Note I'm on Win 11)
I imagine either LG HDR WQHD or Speakers (Realtek) will be the selected output device and you should try selecting the other one to see if that makes an obvious difference. You may want to turn the speaker volume waaaaay down before testing this!
If that works, you can simply keep using that device and/or you can open up Device Manager and uninstall the malfunctioning device then reboot and let Windows reinstall the device and connect the latest driver. That should reset all the settings on the broken device and may restore full functionality.