ScooleySDMF

I took my head unit out to put a different one in, the different one didn't work so i ended up putting the original one back in. Now after i did that, when i start my car only my front speakers work, i get nothing from my rear 6x9's or my subwoofers which are spliced into and powered through my rear speakers, using a Scoche converter box. Then, when i shut my car off, the rear speakers and subs turn on until the radio shuts itself off (about 5-10 seconds) I checked the wires for the rear speakers and everything seems to be spliced correctly, what could the problem be? I also checked and replaced fuses.