amp I bought 3 days ago not powering on - electrical engineer advice wanted

I don't think calling for an update is annoying customer behavior. I would call it caring (anxiously). But of course, if I called every day, that would be a pain and not conducive to fixing my amp. 

My first repair guy in town would take the gear in for repair, charge $150 on my card, with an estimate of 3 months, and he'd call in 3 months with an update that it will be 3 more weeks. Seriously. I think we all want to live by reasonable estimates and timelines.

Yeah I figured as much @devinplombier 
With cars it’s a bit of a different animal. Seems like it’s conceptually the same but it’s not. 
I’ve had a cd player in the shop for almost 6 months. And that’s with me following up every so often. When a tech tells you they’ll call you, they never will. If you don’t express interest it will take a year minimum.  

Yes call the tech @parkergetdean

@parkergetdean 

When you dropped off the amp I'm sure you asked for a time estimate. If the guy said "two months" (what did he say?), then you probably don't want to be calling after one week.

If he called you with an update, then he didn't just toss your amp on a shelf, so there's that 

he said 2 weeks first, to my face, and then 1 week, the next day - for the battery to arrive

I called him - just now, no answer. 

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