Audio Stuttering driving my insane - I've read a ton of threads - but no solution

[rebelloVW]

PC - Dell T7500 - stuttering started happening - probably a month ago.

Was using the rear 1/8 inch audio out to 2 channel stereo. Terrible crackling and stuttering.
Switched to BlueTooth via a BT USB - same thing
Tried simple USB dac type device - same thing
Tried Front headphone jack same thing

I've re-installed the drivers.
Under Device Manager - Sounds/Games - I've disabled 4 nvidea high definition audio entries - thinking this duplication - why 4 was a problem.
Disabled Windows Audio Enhancements
Set Priority for Pandora to High
Removed all handsfree stuff (during BT troubleshooting)

I was going to buy a sound card or external DAC but based on my testing above seems pointless.

Should I try Windows 10?

Thanks for any ideas.

 

[rebelloVW]

I believe I have it fixed.

Tried everything on Windows 7 - even set the Power Options to not shutdown - and for high performance. Didn't help.

I then decided to upgrade to Windows 10 Pro - after several hours - that completed - and surprisingly no issues (static remains):
Dell T7500 - dual quad core XEONs + 128 GB ram.

After upgrade - works fine - still crackle in sound but TaskMgr shows 16 logical processors and 128GB ram - so that part went well for an old computer.

Found more crackle threads - one mentioned bitdefender- I uninstalled that - didn't help. And I turned off Windows AV/Firewall - didn't help.

Tried the latancy app - it pointed to hdaudbus.sys - searched on that - led me to:

https://www.sysnative.com/forums/windows-8-windows-rt/22339-system-interrupts-latency-hdaudbus-sys.html

I made the registry change - and that might have fixed it - but I also went back to power options and disabled fast startup (which wasn't available in Windows 7) - anyhow - one of those two changes helped after the reboot.