<< makes me wonder if it's there all the way through and just getting covered up? This is really becoming an issue and I'm not able to finish projects or other work for my clients because of it. >>

All versions of BIAB have a plug-in that will fix it whether it's only at the end of track or across the entire track.
This is available on any track. There are additional actions available if the track is on or moved to the Audio Channel.

Choose Plugin's and select <DX> PG Dynamics
Disable the compressor
The only control you need to adjust is the Threshold. The other controls are ok for this action.
For this particular track, adjusting the threshold to -21 eliminated the hum. It should be close to that for you too.



<< I muted the track beginning at the previous bar and it was fixed. >>
If the hum is being masked by the other tracks, it will be better to Gate the track.

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.