footswitch problem?

[Fronzil]

..just once and awhile, i'll go to hit the lead channel on my mark iv's fu-3 footswitch, and it won't take until the 2nd or 3rd time...all others work instantly (rhy 1, rhy 2, lead-eq, eq, loop)..only happens once and awhile, i've tried tightening the bolt or whatever that's just around it..still does it the same i'd say

 

[tony777]

Probably a bad connection.
I would check the soldering inside the footswitch.