Helping a friend with his vintage gear!!!!

[Worf101]

My friend Randy's a pretty intelligent fellah... or so you'd think him being a Federal Judge n' laywer n' all. But for a smart guy he does some real dumb chit at times. About a month ago Randy calls me over and says he's having trouble with his rig, so... me being the "right guy" that I is I offer to take a looke at it for him. Randy's Rig consists of the following.

Vintage Turntable (Some shiney thing, I'll get back to you on that one.)
Kyocera Receiver
Big Advents
Generic CD Changer

Upon arrival the first thing I checked out was the speakers. Rotted foam surrounds. Next he was complaining about crackling in his speakers. I went to the receiver and slid up the volumen and the pots were cracklin' like bacon. So off the speakers and receiver go for general repair at the local stereo repair shop (yeah we still got one of those). Everything came back lookin' great the speakers looked and sounded great but after a few days the receiver started crackling even worse than before. When using either the CD or the Turtable an intermittant crackling would be heard from the speakers. It didn't happen when on Radio so I figured it might be connections.
I cleased the connectors with a Q-tip and some rubbing alcohol but no soap. I then had Randy play the CD player all night with the speakers OFF to see if that would help. It helped some but the crackling returns when the gear is first turned on. It eventually goes away BUT it never stays away....

Anybody got any ideas? Any help appreciated.

Worf

[Smokey]

It helped some but the crackling returns when the gear is first turned on. It eventually goes away BUT it never stays away....

This is a wild guess, but crackling might still be coming from volume control since initialy it was dirty and got it serviced. Some residue might still be present.

Tell the judge to turn off the receiver and and play with volume knob (back and forth action) to see it cleans up a a bit.

[stereorob]

Spray the volume pot with QD electronic cleaner. It's cheaper than De-Oxit and works just as good. That should clear up the crackle. Now if it's crackling intermittently even with the volume all the way down you might be in trouble! Could be either a diode going bad or something like that..

[Stevenclarinet]

Dear Worf,
Since I never posted before and putting the cart before the horse, I preface my remarks before doing my profile. As a full time clarinetist, etc., I supported myself working in an audio shop Glen Head L.I. This experience 5 decades ago, had me meet and test gear for the likes of Sol Marantz and many others.
General comments first:
It maybe comforting to keep the familiar, perpetuating the "they don't make things the way they used to" mantra. Unfortunately as your friend knows, most truisms, and many laws are not only misleading, untrue, counter-productive, etc. but no longer serve their original purposes. I restore things like Fairchild turntables, but pay dearly to solve hum and rumble issues.
The receiver must first be isolated, as each pies in his chain needs this connection in another setup. Then if his speaker cabinet is especially good, replace all cones as you intimated. Use one of the 3 or more suppliers that list details electrical, acoustical, and size s/a Madisound. Replace, do not clean the old cables unless they are very special gold laced latnum $50,000. greats from the future. q tips are great for many things, not cables and tape heads. Alcohol has water, and along with the cotton swabs leave debris, making matters worse. Use cleaners meant for this application.

[Hyfi]

My 90s era Hafler Pre did similar and it needed a few caps replaced. But the best advice I can offer these hold outs is too just get something new and be done playing around.

Refoaming speakers almost never returns them to original sound. Re-capping again almost never returns the unit to original sound unless using exact replacements.

It sounds like the guy is in a position to really splurge and drop $2k and be done with it :)