McIntosh MAC 1900/PSB 5T burning smell

@timrhu I hear ya.. I honestly don't think the seller tried to screw me so I'm trying to be patient first. Worst case scenario, I may have to send it back if service cost is too much or I don't get the insurance claim. I'll know in a few days.

Unless their is physical damage to the outer shipping box you will have a very difficult time collecting shipping damage on a 40 year old piece of equipment. 

Is the smell coming from the amp or speakers?

I would strongly suggest disconnecting the speakers, turning the receiver on, and measuring the DC voltage on the speaker terminals to see if it is producing any DC voltage. I know this from personal experience. Since the 1900 receiver is Direct Coupled with no safety (i.e. speaker relay, etc.) if output devices fail it will feed DC voltage directly to the speakers. My Father had a 1900 and we connected it to a set of old Advent speakers. We turned it on but there was no sound so we assumed it had no output. That assumption was wrong because after about a minute of looking around and checking connections, the speakers literally started on fire. The woofer coils got so hot they started the cheesecloth on fire inside the sealed cabinets. We removed the woofers with the cheesecloth burning and dumped water inside to put out the fire. Needles to say the speakers were ruined. I took the receiver to the local repair shop and it was putting out 60 VDC on Left and Right channels. I had the receiver repaired and listened to it afterward and it sounded great, but I used a speaker protection device between the receiver and the speakers from there on. 

Over 40 years units can go bad any minute any time. So claiming refund from seller would not be legit.
Smoke also goes from transistors mainly driving transistors.
I usually ask $200 + high priced parts if overhaul is needed.
I void shipping turnarounds and so advice you do same.
If you’re 1...2 hours of driving from descent tech, you should take the ride and give your unit for repair.
Be ready to stretch to $150...200 ball park. Also some claim examiners are pretty smart so they will note the age of unit and deny your claim.