I have two Stern spike system 2 games Black knight and JP. I got the Black knight before the JP. The front speakers sounded like they were getting low frequency signals that they could not handle. I was thinking that it was just this game as the Black knight has a deep voice that's not the case. I found the same problem with my JP. So I would like to share my solution with the group as it makes it sound much better.
Just add bass blockers to the front speakers and your all set. Here is a link to the ones I used.