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Your problem isn't that it's floating, or recessed, it's going to be something totally unrelated.
Bad studs perhaps, dull knives, posts not locked maybe?
Loose nut? Strings not stretched properly?
The Edge, even with bad studs AND flat knives WILL hold tune when everything else is properly set up. The only problem in that case is when you pull up and release the bar it may come back a bit (or a lot) sharp, but a quick tap down and it will go back to "perfect" tune.
Check out Rich's site before you assume it's JUST because it's floating/recessed as that really isn't a cause of tuning problems.