Do those sounds happen at lower volumes during that scene? Try to figure out if the sounds are coming from the tweeter or the mids. If it is a problem with the soundtrack it should be audible with most volume levels and not just at extreme levels. The problems with the noises coming from the bottom two drivers are solved now, correct? I wonder if the mids on the M80 are run full-range like they are with m60? That can be an intense scene at loud volumes. It sounds like you might be clipping your receiver as well. This is a tough one.
