I have to come in and resurrect this thread. The HeadBox SE on many motherboard line out's will be all many people need. It's not as dynamic as the PA2V2 but it's got a nice smooth sound that is easy to listen to for hours.

You can try an expander like Relife instead of ReplayGain.   Relife: http://www.terrywest.nl/utils.html   Foobar 2000 VST Plugin: http://www.hydrogenaudio.org/forums/index.php?showtopic=84947   In my experience it makes harsh recordings sound smoother and puncher.

The Sennheiser HD 205 are another good choice and work well enough with onboard sound.

For Sound Quality USB Should be fine. Now you said your Usb is dying. How about something like this:   http://www.amazon.com/GMYLE-2-Port-PCMCIA-Cardbus-Notebook/dp/B0027Q4HXG   With this path you will be able to upgrade later.

There are also usb cards such as:   http://www.amazon.com/Creative-Soundblaster-Audio-System-SB1290/dp/B0044DEDC0/ref=sr_1_1?ie=UTF8&qid=1378170585&sr=8-1&keywords=creative+live+go   Or:   ...

Without a doubt in my mind it would have to be Minecraft

Monster N-tune

Sony MDR-V55 (Broken) Koss PortaPro

Monster N-credible N-ergy iems. They sound like a pair of tweeters. mids are muffled and the bass is too.

The NAD C316BEE works fairly well with the Knight series.

I wouldn't say their tinny but they can be muddy