Audio quality terrible...

Hello,

I originally posted these issues in the iTunes forum because I thought it was isolated to iTunes or Quicktime, but this is not so.

You can see the original post here: http://discussions.apple.com/thread.jspa?messageID=9646400#9646400

The audio is severely compressed and sounds like it's had a bandpass filter applied. (no highs, no lows) Additionally, the sample rate may have been affected, as there is a grainy/clipped quality to the audio as well. Finally, the overall volume is lower.

This is true regardless of the audio source; previews in the iTunes store, music in my Library or on my iPod or even playing an Audio CD back in iTunes will reproduce the effect.

This is also true regardless of the playback device. When listening through the computer speaker, plugging in headphones or speakers to the analog audio output, also when using my Harman Kardon USB Soundsticks and I even plugged my receiver into the toslink output to verify there was not an AD converter problem.

In iTunes the Equalizer settings have no bearing on the quality; turning it on and off does change the sound slightly and preamp settings on the equalizer do affect the output level. In Preferences -> Playback, all the checkboxes are cleared. (Crossfade, Sound Enhancer and Sound Check)

I've re-started the machine, zapped the PRAM, turned on/off the settings in the Playback portion in iTunes preferences, reinstalled iTunes and Quicktime... NOTHING has any effect whatsoever.