supernukes,
Welcome to the Side Imaging Forums!
Where you mounted the transducer; is this a flat area or is there a slight curve to it? If it is mounted in an area with a curve, it could cause it to be looser (is that a word) than what it should be.
If it is mounted in a flat area, I would call the Humminbird Customer Resource folks (1-800-633-1468) and ask that they send you a new hardware pack to install as it should not be that loose.