The Cat pump belt will likely be the most forgiving unless you've got the pressure turned way up at low rpm.
One or more of your drive belts may have a "hernia" from overstretched or torn lateral cords. Not fatal, but annoying when it still "looks new".
Why is the belt tensioner not being loosened for belt application? I've noticed several bypassing that step, so I wonder if it's a pita design?
Make sure your blower is flushed out, a dirty blower will drag...even on a Bane.
For lack of a better spec, the general practice is to make sure there is less than 1/2" deflection when you press a belt midway between the pulleys. (I'm not quite satisfied with that answer either).
Your "loosest" belt will squeal first, so until it's replaced just run them all a little tighter than usual. Persistent slipping will generate heat that will attack all the belts on that pulley.