New head unit woes

I have a 2015 Prius v3 and my wife has a 2014 Prius C3. Sometimes I wish I had the C, it's so much fun to drive. We're constantly trying to outdo each other on the MPG front. Not that I don't love the v, but soon after taking possession (end of June this year) I began to experience the dreaded screen freeze ups. The unit even made phone calls on it's own a couple of times! Thanks to everything written here about the freeze ups, I was able to get my dealer to replace mine, although the entire ordeal took about a month, including waiting for the new unit to arrive. I was told this could only be replaced during weekday hours and being very busy at work I had to wait a couple of weeks to make an appointment. The tech rep said I was perilously close to the unit being shipped back so I'm glad I called when I did. (My guess is these are in such short supply they have a time limit on how long they can keep one that is going to be a no-charge replacement.)

Today was the day that it was replaced; took roughly 75 minutes. I was told I would need to re-pair my phone and go through the whole set-up of stations and preferences as if the car was totally new. I didn't consider that to be a bad trade-off for a working unit!

So, when I got home (the dealership is a good 35-40 minute ride from home), I took out the manuals and began the set-up. It took far longer than I anticipated for the Bluetooth pairing, until I tried deleting the pair with my wife's car. That did the trick. Next up, re-setting my stations and other audio settings. That should only have taken a few minutes (I don't switch stations a lot, so have few favorites). I only wanted to set a few stations, adjust the equalizer as well as L-R and Front-Back speaker settings. Got the stations done, but the equalizer and speaker screen was dimmed and wouldn't accept any input. Then I noticed the Volume controls were dead (and stuck on fairly too loud). Neither the dial or the Steering Wheel control would work.

Am I missing something? Have I screwed something up? I swear the volume controls were working on my drive home from the dealership. I'm not eager to trek up there again so soon. Any suggestions?

Thanks in advance for any replies.

Jeff