Subwoofer/Rear Audio help?

So I successfully installed my subwoofer and amp in my 2007 Prius with JBL w/o Nav. Everything sounded fine when I tested it in the garage. I went out that night I did the installation and it sounded great. Only issue was that when I got back in my car that night and started it up, there was no rear audio at all (By rear audio, I mean all four rear speakers + subwoofer).

This continues to happen. Sometimes the subwoofer works but either when I drive for a good 5 minutes, or when I turn the volume past level 06, the subwoofer and rear speakers go out.

Does anyone know what would cause this? The connection with the blue rectangular "molex" port is tight, and the sub tapped the wires correctly to my knowledge (rear right speaker which is the red and white wires on the molex).

If anyone has any ideas or thoughts that may help, they would be greatly appreciated!

Thank you!