I have been trying for untold hours to get 2 pedals programmed properly. I am referring to the pedal on the HD500X, and the LIne6 EX-1 pedal plugged into the pedal 2 jack with a stereo TRS male 1/4" plug on each end. I wanted to have volume on exp1 and wah on exp2, with the wah turned on and off with a fs button. I use setup #1 FSmode: FS5-8. It is beneficial for me to NOT use exp toe switch because I like to have a lot of volume headroom under my foot to get that Terry Kath feedback. If I have exp toe switch programmed, when the pedal goes all the way down to activate the wah, my overall volume is too loud.
I thank silverhead and ratatats for putting me on the right path.
1. I had issues because I was had my foot on a pedal while I was using the HD Editor on my computer while I was sending the selected patch. So don't touch anything on the HD500x while you are making pedal assignments on the computer editor.
2. After you finish programming, switch to another preset and then back to the one you just programmed.
3. If that darn pedal you are using on pedal 2 is not responding, unplug the pedal 2 cord, then plug it back. Check to see that it is now responding. Send the selected patch for saving again. Switch to another preset and then back to the one you just programmed.
These 3 steps gave me success.