Best speakers for compressed audio

Speakers aren't the answer. The only solution there would be to buy something with really low resolution so you can't hear how lousy the compressed file sounds.

One option that some people hold in high regard is the BBE Sound Restoration System -- http://www.bbesound.com/technologies/BBE_MP/

Another option would be to switch to very warm tube amplification or insert a tube buffer stage between your hard drive or source and your preamp or amp.

Active speaker systems like Audioengines 5s and Blue Sky Monitors (EXO) handle compressed files wonderfully.

If you wish to go passive, I can also recommend the
Fatman iTube amp system out of the UK, tied to smaller monitors like the Paradigm Atoms or the PSB Alphas,

Michael try a power conditioner or new AC power cord if your getting interface. Then look into DAC (BenchMark or Bel Canto) if the hard drive has USB output. The DAC will improve Flac sound and mps (depending on the source) and the filter will clean-up the source noise.

Audience Adept Response aR1p $495
http://www.audience-av.com/conditioners/ar1p_price.php

BenchMark 1 $1275
http://www.benchmarkmedia.com

Many dont realize how much dynamic compresion the loudspeaker produces.Sure your source is compressed most music is massively compressed when mastered.Toss in compresion for mp3 or other files and more again if such a recording is broadcasted. But and I know this wont work for you.When a large horn system is used the massive dynamic range the loudspeaker can produce.Makes MP3 or other compressed sources sound better for you dont lose dynamic compresion to the loudspeaker design.The smaller the loudspeaker the more compressed or limited the dynamic range.No free lunch in loudspeaker design no mater what the manufacters of tiny hi-profit mostly made in China speakers tell you.

iPod headphones. ;=oP

Put some teflon tape on your AC plugs.....

Thank you Lapierre. I purchased a power conditioner (which I had never heard of before your suggestion) as it did the trick
! Now I have no interference from electrical and network stuff in the office.

Great. Which power conditioner?