The 30 series units are plagued with bad solder joints.
I worked hours on a 38 once redoing solder joints to bring it back to life.
When you start removing cards it exacerbates the issue.
So be patient and use a 25 watt iron and start touching the solder points on the cards for the header connections.
This could be the issue with the VU meters. I experienced that as well.
As to the reel motor that can be a bad drive power transistor that is mounted to an aluminum strip.
I had that issue on a 32, and replacing that transistor solved the problem.
However before you get to that area work the solder iron on the cards.
Make certain upon replacing cards that you are patient. There are lots of pins on all the card connectors that have to be properly aligned to fit in.
It is no fun but patience will prove a success story.