I got my Sony XBA-1iPs for $30. They come with foam tips so they're very comfortable. Very much recommended.

http://www.amazon.es/Sony-XBA1-Auriculares-in-ear-negro/dp/B007I1QZFI/ref=sr_1_168?s=electronics-accessories&ie=UTF8&qid=1400901811&sr=1-168  ...

There is an incredible deal on the M50s right now that just fits your budget. Word or warning though, it may be too bass heavy for your genre, and the vocals won't thrive as well as you'd hope. Otherwise, it's a really solid headphone.  ...

NVX XPT100s sound perfect for you. They're very comfortable, and do vocals really well.

Apparently the XSs are much more comfortable than its predecessors. They also have more bass and a bigger spike in treble for what I've heard. Not that V-Moda headphones need more bass, but if bass is your thing, then definitely look into these.

vPulse, UE600s, and the Realvoice.

Try a budget amp like the Fiio E6 and see if there's any difference.

Sennheisers clamp too much? The HD280/380s right? QC15s clamp waaayyy harder, if you're talking about anything < HD518s.

It may be because you have lots of interference happening between your soundcard and your headphones. Get a new soundcard or a DAC.

Velodyne vPulse are perfect for you. Also check out the Sony MHC1s, Philips Fidelio S1s, t-Jays Threes (if you really like bass), t-Jays Fours (if you really, really like bass), a-Jays Fives, Nuforce NE-700Xs, UE600s, and the Spider Realvoice.

NVX XPT100s meet the requirements quite well actually. They have a great soundstage for a closed phone. Also look at Sennheiser HD518s and HD558s.

The t-Jays series have some incredible bass. Good for running too. Check out the Shure SE215s too. BTW, the more information you give, the easier it is for others to give help.

I can vouch for the XPT100s. Better sounding and waaay more comfortable than the M50s.

NVX XPT100?

I'm gonna go ahead and say it, the ATH-M50s suck. The cups are too small, the clamping is too tight, the bass eats the mids alive, and there is no soundstage or instrument separation. I tried two different pairs, in case I got a fake, but nope, they are just a mediocre pair of headphones. And...