2000 merc 200 efi warning horn beeps when hitting a wave

[tkms002]

Just this year I have had a problem with my warning horn(the one attached to the ignition switch) beeping when I hit a wave hard. Does not do it on flat water. Did not do it at the end of last year. Any thoughts would be deeply appreciated.
The beep is just a quick beep when you hit a wave hard like crossing a wake. Small waves do not cause this issue.
Thanks

 

[merc850]

Could it be the low oil beeper?, if you're still using oil injection.

 

[tkms002]

Yes it could be the low oil beeper but the primary and secondary tanks are nearly full and it only happens when hitting a wave hard and only for that instant.

 

[Faztbullet]

The float in the oil tank on motor is jarring. Bleed tank of all excess air.