Road King II V2 : volume only with FX Loop 2 active

[Dudeeeeeee]

Hi all,

This is my first post on this forum as I haven't found any answer to the following problem :

Would anyone know how to fix the following issue : on a Road King II V2 head, with the FX loop bypass "OFF" (FX loops are thus active), the only way I can get decent volume levels is by having FX loop 2 active at all time. Activating FX1 while FX2 is active doesn't affect the volume and allows effects to be switched ON and OFF, however with FX1 and FX2 both off I get near 0 volume. Its the same result with FX1 only.

I swapped V5 for a new Mesa branded 12AX7 with no improvement. All power tubes are brand new and Mesa branded.

Any suggestions on what to try next?

Thanks in advance!