So I have Roadster that I blew a 6L6 in about two weeks ago. While I was waiting to get some new tubes I pulled the 4 6L6's from my much newer Roadking II. The Roadster sounded so good with the newer tubes I decided to swap the 6 12AX7's as well. I follow the tube charts in the manuals but when I powered up my Roadster things sounded really bad. Channel 1 sounded fine but when I switched to channel 4 it had no gain. It sounded like an overdrive pedal. Then when I switched it back to channel 1 there was barely any volume at all. So I decided to swap back the original 6 12AX7's but there was no change. I double checked to make sure the tubes were seated properly. I really don't understand what I could have done. Any thoughts how to correct this would be greatly appreciated.