PS2 is dark on CRT TV?

Ok, I have an odd problem here, my PS2 seems to be much darker on my CRT TV than my other consoles. My NES and dreamcast have an extremely bright and good picture, so I know its not an issue with my TV, the rest of the consoles I have hooked up look fine as well. I have 2 PS2's the fat and the slim and both have the same problems. I have the phat hooked up to my HDTV with regular RCA cables (I am out of inputs) and the slim is hooked up to my CRT TV, again with regular RCA PS cables. My CRT TV doesn't have any other choice of inputs. The phat seems to have the darkness issue on my HDTV too, as DVD's played on it look much darker than if I play them through my Xbox 360.

I was playing the game psychonauts, on my CRT TV which I basically couldn't see at all, since the game was so dark. I tried turning up the brightness but that didn't help at all. But some other games have issues too, and some DVD's also look very bad when played on the CRT TV, they look darker on HDTV but the darkness isn't nearly as bad as it is on the CRT. Games played on the PS2 CRT combo in general just look darker and crappier than my other consoles but I mention psychonauts which is a glaring example.

Basically what I am asking is there any way I can reduce this problem or fix it?

Do you have other systems hooked up to the tv? Once my nephew had his GC hooked up and PS2 hooked up to the same tv and the PS2 looked dark. I told him to unplug the GC av cable (even though the GC might not have been plugged into the wall), then the PS2 seemed brighter. It has something to do with maybe the PS2 thinks you're trying to copy a DVD. Not even sure what kind of tv it was, it was small definitely, but not sure if it was digital. They did have an Apex digital one, but that got tore up. So maybe it was when they used to hook both systems up using the coaxial cables. Maybe he unplugged one of the coaxials from the back that was connected to the other one. You know, one on top of the other. Too much information I know.

Edit.
I unhooked the back of his GC (the AV out or whatever it's called). Since we'd already unplugged the av cables from the tv, I think. It's been years ago, like 2002 or 2003.

The PS2 was always darker than the original Xbox and Gamecube, I'm guessing to hide graphical flaws? I always have to turn the brightness up on my TV when I hook the PS2 up. Battlefront II is nearly unplayable on dark maps if I don't.