I've been trying to get similar functionality with Pod HD and FBV3 as Pod XT Live used to have, meaning when wah effect is not switched on, the expression pedal works as volume pedal. I haven't succeeded so far and I wonder if it's even possible with the current firmware and software?
I can make them both trigger from the expression pedal switch and if the patch has one on and one off by default, it seems they work right in that sense: When wah is switched off, vol is switched on. Hower it seems that the expression parameter EXP1 only changes when I have triggered wah on. When wah is off and vol is on, the expression pedal does not have any effect (it won't turn the knob in POD HD Edit like it does when it works).
I've also tried assigning the vol on/off to FS4 in Edit (FS5 in FBV3) and trigger vol separately but same effect. I can trigger vol/wah on and off but when wah is off, the EXP1 does not function.