GUI app to cut audio without (or with mininal) recoding

Question

Audio formats these days typically involve blocks/segments of a certain lengths. I would like a GUI tool to inspect (and listen to) audio tracks, and decide where to cut them, so that either:

• Cuts happen at block/segment boundaries, so that no recoding is necessary, just a transcription of the blocks to a new file.
• Cuts happen anywhere, and only the sub-segment up to the next segment boundary is recoded, so that most of the track loses nothing (if the format allows it, anyway; otherwise, perhaps a coding of a segment beginning or ending with some silence).

Required features:

• Runs on X-based desktop environments
• Runs on Linux
• GUI
• Supports MP3 and MP4 AAC
• (No price or license requirement - go crazy)

Desirable features:

• Gratis
• Open source with a libre license
• Runs on Windows
• Command-line mode
• Seapration of command-line tool and a GUI frontend
• Actively maintained
• Wider range of formats supported

Answer 1

This is what I've found myself:

LosslessCut (GitHub.com)

It's more focused on Video; the GUI is very limited (e.g. can't enter the cut range as timecodes, typing in the digits); and you don't see the wave form or the block/frame boundaries. Still, it sort of does the job.