Fuse? I'll check if they are on their own, gimmie a second.
I'm having a little trouble pinpointing which exact fuse goes to the sub amps using my pile of PDFs on this computer, but open the fuse box in the engine and look for the smaller fuses. I believe it should be 30A, so just see if any are blown. Looks like it might be fuse F16 which is a corner fuse. Unfortunately I don't have an orientation on this diagram so I don't know if it's front or back of the top of my head, but like I said, just check the small square fuses, specifically on the side with a double row of them. I see a couple of those mentioned for audio.
Here's a diagram of the fuse box to help: