[Mart]

That hub/drum looks like a 32-34 to me. They're supposed to be used with 1.5" brake shoes. If you're running juice brakes they're 1.75" wide. I have that setup on my 33. The shoes will rub occasionally, especially when cornering. If something has come slightly adrift it will rub far more readily than with the 39 or 40-48 brake hubs/drums.
I ground some material off the outside of my shoes and it is ok 99% of the time.

Pulling the hubs/drums should reveal what is wrong and hopefully the fix should be simple.

As a side issue, I can't see that well in the video but if they are still there, you need to remove the nubs on that hub if you're running steels.

Mart.