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...

If you're the type of person that listens to the type of music that Beats are intended for (bass heavy music), the best pair are the indestructible V-Moda M100s. Beyerdynamic DT770 80 Ohm, Audio Technica M50s, and the Beyerdynamic Custom One Pros come to mind as well.   It would be easier to...

Whoever told you the NVXs weren't for extended use is wrong, because they're by far the most comfortable cans on your list. Their sound signature is not meant for your genre of music though. I recommend Sennheiser HD518 or the Sennheiser HD280 Pro. The 518s are semi-open so they leak a bit of...

Although the XPT100s/HM5s are closed, their soundstages are great. Just wanted to clear that up. As far as sound goes, indie will sound great but electronic will not. The cups of the Superlux were too small and heavy for my ears. I've never tried the SR850s.

http://www.reddit.com/r/headphones/comments/1vn22f/something_just_sounded_off_about_my_macbook_airs/   Are you having the same problem that this guy had? 

PSB M4U 1?

Superlux HD688b?

V-Moda Crossfade LPs are on sale for $80 on Amazon.ca! This sale won't last long though! I really recommend a pair.

NVX XPT100, and Creative Aurvana Live!. Although if you're not American, then they may be too expensive.

There's a great Future Shop sale going on right now where the Sennheiser HD518s are only $79.99. Closed Sennheisers sound good, if somewhat muddy in the bass. But maybe that's just me. If you're worried about the thin headband of the UE cans, then you can forget about the CAL!s. Same goes for...

UE 6000 or UE 9000. You can pick up a pair of UE 6000s at your local Canada Computers.