No dust on my 536.
Wave Runner- I haven't seen any Phase-2 use yet on the Westy system. It is a simulcast cluster though which could explain your signal dropping in and out. If you do a channel hold does "DAT" remain solidly lit when you are not receiving a transmission?
BCD536HP, BCD436HP, HP-1, BCD996XT, BCD396T, BC780XLT, PSR800, PSR500, PRO197, PRO96, PRO23