Try reseting the defaults and then if that fails re check your BPS setting on your BBS system.
Go to your local site and use a chrono to measure your bps to get an accurate reading.
Check your manual for how to set the bps limit on the BBS system.
Here is the ramp info:-
Ramp 1 (Mode 3 on the Firing Mode Parameter)
This mode allows the rate of fire to ramp to a maximum set by the Maximum
Rate of Fire with BBSS enabled parameter, once the trigger has been pulled
four times at a minimum rate of 5 pps (pulls per second), and allows this rate
of fire to maintained as long as the required trigger pull rate is maintained.
After the last trigger pull, the ramp can be restarted with a single trigger pull
if that pull occurs within one second.
Ramp 2 (Mode 4 on the Firing Mode Parameter)
This mode is the same as Ramp 1 mode but without the one second ramp
restart.
Ramp 3 (Mode 5 on the Firing Mode Parameter)
This mode is the same as Ramp 2 mode but activates at a minimum rate of
7.5 pulls per second.
Have you tried all the different ramp modes? and your gun on semi? Check that you can actually reach 15bps in semi or the other modes.
Also, im no expert, but have you tried changing the battery? a pretty simple thing but I have gotta check
Hope some of this helps!
If you have further trouble PM Lovetone, he has helped me alot with my Etek.