I pulled the grill off of my Rumble 115 cabinet to observe the speaker under power. It seems to me that the 15" is pulling inward when I play my bass thru it. The ports are blowing mass quantities of air out of them during this and the speaker seems to want to fart out really easily. I have the Rumble 500 amp pushing it with all levels at 12 O'clock except the gain and master are at 9 O'clock I wonder if the polarity of the speaker might be reversed. I doesn't look like the speaker has ever been removed since the manufactures assembly, but I'm not sure as I am not the original purchaser. Should I reverse the wires or just assume this is proper. Any Ideas will be appreciated.