So I have a GK 700 rbII. and a p-bass and an active 5 string. And It blew out 3 speakers in an axl faultline supposedly 600watt rms cab. Granted that cab was a piece of junk so I wasn't that surprised. So I picked up a Rumble 410 V2 500watt rms and it sounded fine for maybe 2-3 hours of use over the last month. In my bedroom. I went to play it today and it kept rattling. Ive narrowed it down to the top right speaker. If I rest my hand gently on the cone it stops. So I took the speaker out and gently pressed and prodded everywhere with my flashlight and I cant find anything unglued or damaged. Pressing on the cone doesn't grind or scratch. Pretty sure it is blown though. Am I doing something wrong? how can I blow 4 speakers in 2 high watt cabs at bedroom levels?