integrated amp problems


i have a cheap Yaqin MS-20L integrated tube amp and need some possible solutions to a problem. i noticed over the past 2 weeks that the center image of music was pulling to the left side. well today i did some testing and surely enough the left side is 3db louder than the right. i measured with a test tone and a spl meter 1 inch from each speaker's cone. i swapped everything from left to right{speakers,cables,ic's,all tubes} and the left channel still has the 3db gain. i also noticed there is a little fuzz when i gently play with the volume control. any ideas on what the issue is??
rayray8
I'm not a tube guy, but could BIAS be the problem?
Is this amp auto-bias? Any easy way, like test ports, to check it?
Did you try to swap tubes from one channel to another?
Swap than driving tubes as well and see the result.