blue angel pop when taken off standby

Hi,

just recently my blue angel has started making a pop sound when i flip the standby switch to on.
its not real loud so wont damage the speakers. When i take the amp off standby it pops about a second after. It still sounds as good as ever though when i play it
I got the amp second hand a while ago and the volume knob has always been a little noisy.
Should i be worried about it?

thanks for any info.

Can't offer any answers but my Subway Blues has always done the same thing. Scratchy volume pot too, despite using pot cleaner spray...

I took mine to an amp repair guy yesterday, I'd rather have a small(ish) bill than a big one if it goes in a big way.
He's going to have it apart and give me a quote. Will post back when i got more details about what the problem is.

got the amp back today.
its all good,
he cleaned the pots and gave everything a check over. the scratchy pot has been fixed
the pop was a bad tube in V1 position, he put a new one in there and its all good, actually i think its less hissy than it was before so i'm well pleased with that .
only played it for a couple of hours so its still early days, but so far i'm real happy.

Be aware that there is a highly unusual design quirk of this amp regarding V1. The second half of the tube is configured as a cathode follower - it's not actually used in the circuit, my guess is that it's a left-over design element that was put in during prototyping but used not in the production amps - since in the Maverick, it is used, in 'Fat' mode... but the Blue Angel's Fat mode works differently. Anyhow, being a cathode follower - even if not in the audio path - means that it is hard on tubes, and you should not use a Russian-made 12AX7 in this position since they have a high failure rate when used in cathode followers. So if the new tube is a Sovtek, EH, 'Tung-Sol reissue', 'Mullard reissue' or any other Russian tube I would get it out of there as soon as possible. The standard cheap Chinese tubes are fine! As is any NOS tube, and as far as I know JJ.

Another good way to reduce the hiss is to replace V2 with a 12AY7. This will also lower the gain and reduce the midrange-heaviness of the amp, if that's something that you would prefer. Do not use a 12AY7 (or 12AT7) in V1 since they also aren't capable of taking cathode follower voltages. (By design, including NOS ones.)

thanks for the advice!
its a JJ, i think it should be fine, hes a very experienced tech and really knows his stuff, and hes warratied it too. i'm picking up a pedal hes modifying next week so will check that hes aware of all the stuff you mentioned.
think i'll try your tip for the 12ay7, not that i'm unhappy with the sound but i do like to tweak would an electro harmonix one be good for that or do you reccommend a different brand?

thanks again