stereo is crapping out on me

here is the problem, my cabin speakers will cut out whenever i use my sub. the whole system was put together by my friends and i a year and a half ago, and worked perfectly until about a month ago. the cabin speakers will work perfectly fine if i turn the sub off through the HU. if i turn the sub on through the HU, the cabin speakers will crack, and eventually the amp for them will go into safety mode and cut out for a couple seconds. the sub will work perfectly fine throughout this though. im wondering why the sub is able to affect the cabin speakers, even at low volume. i was thinking it was rattling a loose connection, but it happens even at low volumes. the cabin speakers work at any volume, as long as the sub is turned off through the HU. i have a pioneer DEH-P4300 head unit attached to a 4 pioneer amp powering 4 pioneer 3 way 6 1/2" cabin speakers and a JBL amp and 12" sub. i havent had time to try another amp for the sub from a friend yet, and none of my friends have another 4 channel amp for the cabin speakers. any insight on this would help out a lot.

i would try rewireing everything but to tell u the truth i think ur problem is in ur head unit. Try using someone elses HU and if it doesnt do it then u solved ur problem. Try a diff. HU then let me know what happens.

well i decided to simulate driving with each part of my stereo my shaking it around to see what was broken. turns out that tapping the amp caused it to cut out. took it into best buy today to use the $25 4-year insurance plan on it, and pioneer would rather pay them to fix it than give me a new one. that means 3-5 weeks while the send it somewhere and resolder some part on it. oh well, still cheaper than buying another $200 amp. i can always just listen to the sub without any cabin speakers, if i suddenly get the urge to be retarded.

sorry to hear that. For the 3 weeks go buy a new cd player and when yours comes in just return it n get your money back lol. Let us know how it goes when u get it back