Sennheiser CX 500-B In-Ear Stereo Headphone

NOTE: I found these Earphones on the floor on my way to school, The price listed is the price they appear to be going for now in the UK (online). With regard to the volume control, it could have been damaged prior to me finding them so it may not be down to Sennheiser.

Bass, mid, treble:
When I first put these in I thought "wow! too bassy" (Sony NWZ-B152 - no equaliser). However after adjusting the equaliser (it's not a very accurate one) I can now say that the sound is brilliant. The bass does not overpower the mid and treble but is there and appears to be very accurate and does not distort.
The mids are powerful and perfectly clear, they have a clear 'punch' and for me complete the sound, guitar sounds great.
The treble isn't weak but appears to be slightly less clear than the mid and bass, but I think with a better equaliser this could be smoothed out somewhat, on my MP3 the treble is either too powerful or a little too weak due to the equaliser.

Volume:
These earphones are plenty loud for me. I can't leave them on max for more than 2/3 songs as my ears will begin to ache. I've noticed no distortion so far, even at maximum volume.
TIP: If you feel that the volume is low then try repeatedly turning the volume up and down but don't be too rough, as with many rheostats there could be dust or something stuck in there that needs to be dislodged.

Other:
Be careful with these in as all but the loudest sound is inaudible when these are on, I can only just hear conversation with them in, but not playing music. This makes them great for blocking out noises on journeys but will kill your awareness, so take one out when crossing the road!
The cable is plenty long and seems sturdy, I don't think it will break easily with day-to-day wear and tear.
The volume control on my pair does its job but can crackle and cause one channel to drop out while changing volume, it is also very sensitive towards the high end, while being the opposite on the other end (not very responsive).

I listen mostly to rock and metal but occasionally put on some dance, pop, drum n bass or classical; They all sound great.

Verdict: I recommend these Earphones.

UPDATE [09/03/2012]:

I have been experiencing some more problems with volume dropping in one ear (left) but quickly solved this by turning the volume up and down; I think there was something stuck in there. Very rarely I would have to fiddle with the area where the cables split to stop crackling but I think this was down to some rough treatment from the previous owner.
Last week while holding the buds I dropped my MP3 player and this was enough to dislodge the wire from the splitter so now they're broken, however as I've said already I think this was the previous owner and they were found on the floor after all . I’ll try to fix them at some point.

I won't be taking off any points for this because I don't know how they were treated before I got them, I'm probably going to buy another pair because I loved them so much .
I still recommend these ‘phones.