Miles Sound System (MSS), formerly known as Audio Interface Library (AIL), is a sound software system primarily for video games and used mostly as an alternative for low-end audio chipsets.

It was originally a middleware driver library for soundcards to use in DOS applications when no viable alternative was available.

The 1992 AIL version 2 for DOS has been released by John Miles as open-source (public domain without restrictions) in 2000.

[2][3] The package can be found on his personal site (KE5FX.com) and contains source code for both real-mode and protected-mode programs.

The Miles Sound System was used in its history by over 7,000 video games across 18 platforms.