Ideas/Opinions to toss vs fix RDV995 w/transformer buzz

[Rotel4Life]

I've had a RDV995 for many years and didn't use it for maybe a year or so. When I plugged it back in, there was a faint buzz- a very typical AC/DC transformer buzz. Then when I turned it on there was a LOUD buzz. I popped the hood and didn't see anything obviously cooked, no notable odors. In some other gear I'd just swap it out (like I did a week ago for my home furnace) but here's my thoughts:
1. it still works, so xformer isn't blown and
2. may not be the xformer itself but something else making it buzz so replacing the xformer may not fix issue
3. connections are many and it looks like EVERYTHING has to come out to get to connections- no bottom access on chassis
4. it's a big (sweet) looking xformer and likely very pricey IF I can even find one
5. I hate tossing good gear but I think it'd be a huge headache and just one part may cost much more than I paid for it.

That all said my father-in-law is an EE, visiting for a few weeks and loves tinkering with such things and would be happy to do the work. So I'd love to have a pro or semi-pro opinion on whether or not it's the xformer, or could it be like a pwr filter cap or something else much cheaper and easier? And are there any diagnostics?

[Stoney]

For what it's worth, my first guess would be power supply caps.
Edit: Should have asked more questions before answering. I assumed the loud buzzing was coming from your speakers, but after finding out that the rdv995 is a DVD player, I have other thoughts. It would be unusual for a transformer to go bad from sitting for a couple of years. A transformer under extreme load would possibly buzz loudly, but in that case I would expect the input fuse to blow. Did you try powering it up with the cover off to confirm the buzzing was coming from the transformer? Could the buzzing be coming from the drive mechanism or door mechanism?

[madmac]

Another thing you can try is to plug it into another power outlet to rule out a power issue.

[Rotel4Life]

Tried different outlets, all the same. Yes, cover off and coming from xformer for sure. Very distinct tranformer buzz. Tried loosening nut and retightening- no effect. Slight (electrical) buzz when unit is off and loud buzz when it's on. By 'loud' I mean heard at maybe 10-15 feet. With power off is maybe only heard by folks w/good ears (my wife or mom likely ask "what noise"...). But with power on it's noticable for sure. No sound from speakers- in fact it's not connected to anything but power. Transformer is so beefy and no deteriorating parts so I kinda doubt it's xformer itself. But I know caps (esp 10-15 years old can have a chance of breaking down) so I have a feeling it's a component that controls or filters the xformer. I'm a quasi-amateur EE, so kinda talking out my rear but I know this unit will have a power filter cap- top of my list for culprit. But may also have other 'controller' components?

[mjb]

If you're sure the buzz is mechanical, the options are:
1. Make sure its mounted and held together securely. This obviously depends on the transformer design, in the old days they we're screwed together, now they're pressed.
2. If its an open design, you could try covering it in varnish. Obviously wait until its totally dry before powering up again!
3. Contact Rotel for a new replacement transformer.
Option 3 is probably the most sensible!