TOV pops and crackles

[thinskin57]

i just took delivery of a '99 Tremoverb combo. the tubes are original as it came from a "home" player. after playing it for a while i started to experience crackling and popping sounds. this happens on both channels, and they seem to happen when i dig in on the lower wound strings. i'll experience the popping and crackling for a while, then it stops and will come back eventually. i should probably mention that the amp is dead-quiet when i'm not playing. i can leave my guitar's volume full up, w/the amp on and there will be no pops and crackles. so it's definitely "attack" dependent. now, obviously i realize the tubes are 10 years old and it IS my intention to replace them all immediately. it's just that it's the weekend and i won't be able to order the new tubes until monday. just wondering if anyone out there can verify that full tube replacement will remedy this problem. if the tubes don't fix it i would imagine filter caps would be the next thing to check, but given that there are no pops and crackles when i don't hit the guitars strings, i'm banking that it'll HOPEFULLY just be a tube issue. anyone out there agree?