Why does my site's "streamed music" sound like sh*t?

....when the songs start they sound okay....but when they get to a chorus....it sounds like compressors kicking in hugely .... and makes it sound like crap. I use basically.....a small amount of compression with ozone......then.....I use an eq program called Harbal....that has some kind of auto limiter in it.......which I use in my final step to boost the volume somewhere around the norm. (which yeah....is loud)...but.....anyway.....when I play mys songs.....without streaming....or on my own system......they sound good to me.....but when there streamed like on this site......they sound like shit......soooooo, am I over compressing......am I way to freaking loud???? What?

Too many questions... 

Hi Bluz......there just 128 kbps mp3's. I haven't put them on any other site is quite awhile. Soooo....nope. I don't know if the site compresses them any more or what. I got a life time memebership on this one....and it's a forum I fuck around at all the time.....sooo, that's why I use this one....but....I have to figure something out......maybe do a quieter mix for this place or something.....either that or.....(shutter)....I REALLY DO SUCK AT THIS QUASI MASTERING STUFF.