Line twist?

Hi folks
I have been having trouble with line twist & large tangles with my spinning outfit. I had it spooled up with braided nylon, I really liked the sensitivity it had but, every once and a while I'd get a big tangle come off the spool & have to burn 20' of line to get rid of it. I also found it kinda of a pain having to tie on mono leader. My buddy blamed that "damn braid!" so I stripped of more of the nylon & filled it the rest of the way with 8lb mono (so I could keep fishing) The mono eventually did the same thing.
Now I assume this is due to line twist ( cased by the spinning reel? ) So do I need to have a swivel installed before the leader?
Opinions? thanks
its not always necessarily line twist that is causing your line to knot up. It could possibly be becaue of the way you are spooling your line on the reel. Another is to never close the bail with the reel handle. Every time you cast always close your bail with your hand.
What Nick said.

But assuming you did those things, yes, a swivel will help with line twist.
I've never had that problem with braided line. Hmmmm. A swivel would certainly help with line twist. Is it a cheap reel? Reel quality can make a huge difference and save you the frustration and headache that comes along with a cheaply made reel. Well worth the investment IMO. Also a good quality line. I've experimented with mono, fluoro, and braided, and found that braided was the best. I don't even use a mono/fluoro leader, if the water is murky (mostly is where I fish), I don't see a reason to use a leader.
Thanks for the help guys, I'm useing a Shimano Saros 2500F, going to put the braid back on & use this trick ( once and a while.
Forget the braid....

How deep are you fishing. Just use 8 Seaguar Invisx, if ur fishing deeper than 20ft use a swivel. Also how often do you change the line? That would have a huge factor on ur line quality. Lastly, when you spool line especially fluorocarbon, if youre using a machine, the metal thing can heat up your line making the structure lose its original element.
Thanks everybody for your responses, I think I had a few things wrong. 1st I had to long of a mono leader & when I'd reel all the way up & cast the knot where the braid & mono were connected would "grab" & pull a rats nest off of my reel. I have shortened my leader & have started to close the bail with my hand & I pull the line tight on the spool before starting my retreive.
Use an alberto knot for your braid to mono/fluoro connection and you won't have problems with the knot going through your guides.

There should be a video on how to do this on YouTube.

EDIT: just noticed that you were using a spinning reel. In that case, shortening your leader so that the knot doesn't reach your reel would do the trick, as you've discovered. I do the same with my baitcasters... 5-6 foot leader.