Unison Simply 2, 2xEL34, and 2x 12au7. All tubes light up. One side has no sound. One EL34 tube, blue light inside goes...dim, bright, dim, bright...and gives a buzzing sound in sync with the glow. Swapped the tubes around and problem stayed on the same side. Changed 2 of the smaller caps near the tube base, still no sound. Should I change the rest of the small caps, or is it the big power caps? Appreciate the help.