Artifact filtering

Is there a way to filter or remove artifacts from poorly-compressed audio?

Unfortunately, not at this time. While it is true that compressed video can often use filtering or post processing during playback to improve image quality, the same cannot be said for audio. Video can be smoothed out, but audio cannot. There is also no data that can be recovered from the compressed audio--the artifacts are present because the original data isn't there anymore!

The following Hydrogenaudio thread has more information: MP3 Post Processing