Hey just installed a brand new audio system in my car which included a Clarion 12” dual 4ohm coils sub at 500Rms. Had my amp tuned by a professional shop yesterday to finish the install. Sub worked perfectly and today I showed a friend, popped the trunk and he put his hand up against the sub while it was blasting. After that the sub sounded bad and when I tested the coils with my multimeter the resistance kept jumping (12,22,1,0,17) and so on, on both coils. Could him putting his hand on the sub blown it?