Thanks for your answers, I haven't had the occasion to fly on this particular helicopter, engineers tell me that the "fluctuations" situation has been cured in changing the transducer ( common cause of NR small fluctuations) and the problem of this jammed FFCL didn't come back since that.
I don't think it's an old software problem since our helicopters have been modified some time ago.
I don't think neither it has something to do with the "transducer"
When we have a look on schematic diagramms, the resolver (metering valve) seems indeed rigged to a linkage common to manual and automatic modes.
Well, I am going to PM then, if I can get an explanation has I had on the "mixing unit"
....I like this feeling of beeing suddenly enlighted !