V4 and V5 plate currents

[Black3]

Was hopeing someone might give the ok or a suggesion on what might be going on. I have just finished my JTM45 and had a few issues in start up. I kept blowing a main when I started to drive the amp hard. I do believe everything is straight now after arcing a few tubes out I realized the strange hook up Heyboer provided me on how to hook a rotary impedence swith up with their RS clone OT (fixed at 8 ohms now) and the use of a UA Attenuator just created a high Flyback volatge and I was getting a internal arc over in a Power Tube. I have the Amp up and running now and it sounds really nice with B+ @ 450 and my plate currents at 34ma apiece at Idle on KT66's. What is strange that is worrying me a litlle is I will patch High 2 to the Low 1 input and play out of High 1. Normal volume at 8 and High Treble at 4 real nice sounding drive but after I played 3 or 4 minutes I checked my plate currents again finding that V4 is at 34ma but V5 is at 25ma and will get lower if I play more. If I let it sit for a few minutes V5 comes right back to 34ma again? I tried swapping tubes and found this is exclusive to the V5 socket. Is this a normal? Does V5 tend to unload abit after it gets played and will come back after you let it rest a minute or 2 or do I have someting breaking down somewhere? The amp is just as quiet as can be and except for that V5 issue...The amp is a real tone monster. Sure would like to put my mind to rest on this and box her up, any help would be greatly appreciated
Regards,
Black3

[Reeltarded]

Bump it up.

Did you ever figure this out?