I retubed my preamp with little change. I put in Mullard AX7s. I am wondering if V1 was replaced with a AU7 with 1/5 the gain if it would make a difference. I have read that it brings this issue under control but kills the green channel. I will try it. I am pretty annoyed with this situation. Waste ...

I have this exact same situation. Same fizz, same choked attack. I am trying to narrow it down. Did the OP get it fixed?