Is the FX in that slot set up as an “insert” to a channel or buss? Inserted FX don’t use sends and returns. So while the FX return may have been set up previously (and I don’t think it would automatically disappear from the surface), the fader wouldn’t actually be doing anything.
Hey Brian,
Came back to reload the file and investigate.
Good thought, yeah. Confirmed that the slot is FX bus driven and comes back to FX return.
I tried assigning it as insert, and that did indeed make the FX “invalid” again, but I could not assign to surface strips. So I’m not able to recreate the issue…… Damn.