Chosen Solution
Replaced battery successfully two days ago. Now hearing an intermittent crackling static sound. The speakers are working fine. Update (03/02/2021)
Finally got something to upload properly. I can also report the MBP is running hot when I am on a website. Update (03/02/2021) I skipped steps 6-46 when replacing the battery.
@chasgardner - Happy you got the vid posted! What I can tell you it’s clearly a discharge event which the audio services is picking up. Also the fact you are also noting your system is a bit warm is troubling as well. Let’s get a deeper look at your systems temps. Install this great app TG Pro hopefully we can get a clue where things are messed up on your logic board. Once you get something post a snapshot of the apps main window here so we can see things too. You’ll need to adjust the window size and de-zoom the window to get all of the sensors visible in one snap. Otherwise you’ll need to scroll the window to get the sensors at the bottom visible in a second snap. Last question did you pull the logic board out? You may want to review the mounting screws in Step 29 to make sure you’ve put them in the correct placement [MacBook Pro 15" Retina Display Mid 2015 Logic Board Replacement
