Slight "Crackling" noise in right channel of amp

Hello - I just picked up a Musical Fidelity KW500 integrated and it's sounds amazing. However, when I stopped playing the music, I noticed that with the volume dial at about 50% and no source playing, there is a crackle noise that comes from the right speaker. It's not extremely loud, but it's loud enough that I can barely hear the 'crackling' from my listening position (7' away) if I listen for it. The other channel has noise if I get up close, but it's constant and it should be.

I have swapped cables and replaced cables to confirm that it is definitely the amp channel that is the culprit, and not the speaker.

Now, the music sounded amazing, but because of this, I can't help but think that this is taking away from it somehow and that it could sound even better.

Does anyone have any idea what might be the cause of this unwanted noise? I plan to call Musical Fidelity on Monday but I'm just fishing for thoughts/ideas in the meantime.

Any feedback would be greatly appreciated.
You don't mention the rest of your system. In my experience aging tubes (pre-amp?, source component?) can exhibit a "crackling noise". If you have vacuum tubes in your system, check them, or try replacing with tubes that are known to be good.
Yep, sounds like you might have a tube failure in the right channel. Those tubes were supposed to last for 100K hours I think, but that doesn't mean they won't fail pre-maturely. It might also be a cap or something, but 'tube' is so logical. I'm sure MF will clue you in, and I do believe they have a service rep in the USA (if that is where you live). BTW, I suspect that these tubes would have survived a transit, so it is quite possible it was a bummer when you bought it. Good luck.
Check the tubes.
Maybe you can flip/flop the left and right tubes and see if the problem travles...This will tell you for sure..I does sound like a bad tube though..
This is an integrated with a tube pre-stage so I suppose it could be the tubes.

But let me elaborate a bit on the sound. "crackle" may not be the right term. If you think about what it sounds like when you turn your amp up with your source off (like a hiss from the tweeter, smooth static). It sound like that except that it's not as smooth...there is some kind of sound artifact mixed in with that hiss.

I will call MF, but my understanding was that the tubes were not easily replaceable in this unit so I'm hoping it doesn't mean a trip (and fees) back to MF.

Oh well, thanks for everyone's feedback. I will check with MF on MOnday and hopefully get an idea of what's going on.
If you have another source say a CD or DVD player, connect that source to another input of your Musical Fidelity integrated and see if the crackling or buzzing sound is there. I have experienced this before and the intermittent crackling sound is from one channel of the speaker. The culprit turns out to be the CD player -aging caps. It's more difficult to troubleshoot where the sound comes from if you have more components in your system. I've looked at the power supply, cabling(power cords), tube preamp and CD player before coming to the conclusion that the latter was at fault. If it's not the CD player then most likely it would be the Musical Fidelity.
Hello Fatghost,

I had a somewhat similar problem with my Manley Stingray-also a tube integrated-not that long ago.
It turned out to be a bad capacitor in the Stingray.
Good luck!
Don't place your cell phone near the speakers.
Unfortunately, it makes the noise when there is no source hooked up to the integrated at all which is why I think it has to be something in the MF itself. As for the cell phone, I try to never take that into my listening room...just another distraction :-)
I had the same problem. It looks like this might be a somewhat common problem for KW500. I sent it to Signal Path and they replaced a tube. It fixed the problem. Have since sold it to go to EMM straight into Pass 350.5.

Walter Shields
I think your KW500 uses 6SL7s in the preamp section. These tubes have high gain and are not as quiet. Do follow the suggestion of swapping tubes from side to side. If the noises follow the swapping, then it is quite obvious.

If the noises are indeed from a bad tube, order some tubes from a reputable dealer. Some people here stated that they had good experiences with upscale aduio. With 6SL7s, I would order platinum grade to get lower noises.

Hope it helps.