OK, with the PIOs in place while the reading is a little erratic, one reads between 25mv to 35mv and the other between 2mv/3mv and 15mv
The Duelunds were mounted underneath the PCB while these are mounted on top, I guess that has no bearing on the readings, does this mean the VSF's are stuffed?
OK, no strange woofer action when adjusting the volume now, but DAMN! Russian PIOs are no substitute for VSFs
Edit: hmm...I'm still wondering if the issue was mounting the caps on the underside of the PCB
Edit part 2: I'm near certain that it was the mounting on the underside that was the issue (nothing else makes sense to me), picking up interference, but no where else to mount the VSFs. The PIOs are OK but a definite step back. looks like I need to rebuild this thing soonish, that way I can construct it point to point while at it.