Velodyne DD15 - worth repairing the plate amp?

It's a great product if you want a simple way to set up subs that don't have built in room correction.

Minidsp does more but requires a computer. Once set up it doesn't anymore though.https://www.minidsp.com/

How good is my Audyssey built into my receiver setting up the sub in my room?

When using the built in plate amp, should I set up with Velodyne hardware/software (and how to disable Audissey/Receiver for the sub only) or switch off Velodyne and run full Audyssey? Or both. I need/want to run Audyssey for the other channels (I do listen to SACD and Stereo). Receiver on my office system (where DD15 currently is used) is my little Onkyo TX-SR353, which uses AccuEQ:

Onkyo TX-SR353 comes with AccuEQ room correction system and includes the calibration microphone.

• AccuEQ: First, AccuEQ detects the presence of speakers and evaluates the impedance of each. Next, it pinpoints their distance relative to the main listening position using the mic and sets suitable sound-pressure levels. Then it selects the optimal crossover frequency so that deeper bass rolls smoothly off to the subwoofer. Finally, AccuEQ performs frequency response equalization based on room-acoustic and speaker data collected via microphone. The sound-field is now tailored around the listening position, resulting in a more immersive and realistic in-film experience.

Usually, unless things have changed, Audessy doesn't do that much to equalize subwoofers. And I would also assume that Velodyne's EQ works more closely with it's internal amp. But I could be wrong because miniDSP is supposed to work great for subs.

Goood to know. Looking forward (hopefully soon) to get plate amp back from EBC and do a comparison switch: Audessy with external class H amp vs built in Velodyne optimization and amp. 

What settings on the receiver do I need to choose when running Audessy for 5.1 (on the 5 and not the 0.1)?

I would just run Audessy normally then go into to manual setup and set the sub's xover higher than Velodyne's internal one. Adjust mains if possible to match the sub.