Tonight, I was giving the 8900 another go by working on quilting the quilt I've made for DH, and the thread broke (it happens). Since I knew the machine had been used at QuiltCon, I decided to change the needle before rethreading. Can you believe that completely solved the noise issue?! I am pleased and irritated at the same time. LOL Pleased it's fixed, irritated I never thought of it myself.
Now I'm really excited to put Ricco through his paces and see how he does!
Thanks to everyone who made suggestions!
Skratchie