E-brake rattle. What to check?

[jabstick420]

Have this sort of rattle/droning that starts at certain speeds and can become slightly annoying.

Just adjusted the e brake in hopes that it would remedy the problem but it's still there.

Clicking the hand brake to the first click eliminates the sound completely.

Sound is audible in the cabin.

Any ideas?

I thought for sure taking out the cable slack would solve this issue...

[Ricky Bobby]

Are your adjustment nuts loose or the bolts at the base?

[jabstick420]

I snugged the lock nuts to the adjustment nuts...

What are the "bolts at the base"?

Base of the e brake assembly?

[jabstick420]

This was happening before any adjustment.