I have noticed this also on my Speedster 200. I assume that the 2 x 2 short beeps are the OK to start the engines, although on our last boat, 1997 Challenger 1800 w/twin 110, it would just beep twice for both engines. I have no idea what the long beeps are for, but they sure are loud and annoying. I will ask my dealer when I take it in for the 10 hr. check.
I just picked up my Speedster 200, and everything worked fine at the dealership, (the normal 2 beeps when the DESS cap is put on) but when we got it home, and put the DESS cap on the post, I got 3 long beeps and then 4 short beeps. The 4 short beeps kept repeating. The shifter was in neutral, and the engines would still start.
I don't see this code in the troubleshooting guide in my manual, so I wondered if somebody could tell me what it means.