FX problem- suddenly not working

I have been using my QU PAC now for a couple of years and for one particular band, I have had the same settings in a scene that I use as a starting point for each show. I use FX1 for verb, FX2 for delay and 3 and 4 for special FX.
I used the scene last week and had no issues. Last night everything was working (or so I thought) but when I went to pull the fader up on FX4, no effect. I couldn’t not get FX3 or 4 to work. No metering showing signal on either mix.

I have it set up today at home and I cannot work it out for the life of me. If I use a different band scene, I get all the FX I need - similar thing using 3 and 4 for special FX.
I go back to this bands scene and no FX.
I thought it might be a corrupt scene and I have a secondary (back up) scene for this same band in memory too and cannot get the FX to work on that one either.
I have checked routing, gone back and forth from a working scene to this one checking every setting I can find but no luck… Any ideas anyone ???.. thanks you.

Well… as soon as I stopped typing… I found what was wrong… couldn’t see it on the iPad but I am sure I checked there yet I see it on the QU PAC… For some strange reason the input shown on the engine back panel had changed to a mix on both of those FX. I have no idea why but I am happy I found it. Crazy stuff… thanks anyway everyone.

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