I've got a 94 Deville. I changed out my stereo and put a new cd deck in. Wired everything up properly with an amp and 2 12" subs in the trunk. SOUNDS MINT! Untill i close the trunk the all of a sudden it sounds like the subslost all there power. Open the trunk back up and sounds great. Wondering if the power trunk close/release mecanisim is a problem to whats happening?

 

It's always going to be louder with the trunk open when you stand outside. I don't know exactly how much louder or how quiet it is when it's closed, but you might just have to increase the gain and the bass boost on the amp so it sounds good when the trunk is closed. It should be up about 50% - 75% on the amp. Check to see that your RCA cables have a good connection on both sides. You might just have to play with the amp to get better sound.