Some alternatives to SDL?

I tried to roll my own alternative, but it's a way bigger undertaking than I initially thought.

I have a quite decent audio system for Windows/Linux (MacOSX missing due to lack of hardware), so I can just skip that, if it relies on "variable size" buffers or its only audio capability being "function that plays WAV/MP3 directly". DLL/SO preferred. I don't need duplicates of things that are already in any standard library.