This is a post from audiodyi.com. I'm having the same problem. Apparently this is fairly common in the D290. Anybody experience this and found a solution???
What was just an irritating problem with my delta 290 integrated has now become serious.
The input select dial produces a real hum. Switching back and forth used to sort it out, but now it does it all the time.
Ive read others who've had problems with this pot, and soved them, apparently by cleaning it. Its a motorised selector, enclosed in a housing, which is itself soldered to the pcb...
Any further info would be appreciated.
BTW... I got this integrated about a month ago off Audiogon for $325. It is worth EVERY penny despite the little unexpected issue. I know there's a lot of "Best integrated/amp under $1000 (or so)" threads and I must say, this one is a stunning value at current market price. Loads of detail, very precise, slightly warm presentation though very clean, NEVER fatiguing, nice n smooth. Very distinct soundstage after wiring with Kimber 4TC (speakers are Axiom M3Ti - and I never knew they could sound THIS good). NAD C350, Cambridge A500, and the likes sound like crap in comparison. Though in the sub-1k used category I'd definitely give the Classe CAP-80 a whirl....
Had my arcam for 10 years now and had the same problem constantly having to wiggle the selector knob to get the desired channel to work correctly with no crackling or humming, contacted ARCAM but part no longer avaliable so just sprayed loads of electrical spray into the actual selector withthe motor connected to the side wiggled the selector several times and now its fine.
I had the 290 for a long time and recently traded it in for my speakers because after buying the Sugden for my bedroom I was surprised that despite being older was superior t the Arcam.
I never had this problem with the Arcam though. The only problems I had was the remote control's paper cover fell off...the glue stoped sticking...no biggy and a speaker connector got stripped...again really cheap.
I did get a bit of grit when switching inputs though. It needs to be cleaned. My Sugden now also need to be cleaned because on some of my inputs the soudn out one channel gets cut completely...just out my AUX 1. Bit of a pain to take it in for just that...so I put the dvd player into the tuner ins cause i have no tuner anyway.
It's the nature of older gear that nagging things need to be done. If the cost is too high I would consider purchasing a preamp and use the Arcam as a power amp. you'll have to take the cover off and manually switch the 290 to work as a power amp though which is a bit of pain in the neck. I used the arcam as a power amp for my headphone amp with some good success. With a "good" dedicated preamp I think you'll notice the sound really open up. you 'll be basiclaly converting the 290 integrated into a 290P power amp. This way the Arcam's preamp is taken out and you have a no moving parts power amp which should be noiseless for another few decades.
This is all under the assumption you have the bucks for a preamp...but you should weigh the costs of fixing it.