The old shareware game Darwin's Arena has both CGA and Tandy versions. The Tandy version uses 3 voice sound and white noise. It ran flawlessly up to and including version 0.74. Somehow the patches made on 0.74-2 have introduced a high-pitched noise that lasts for a few seconds after every use of Tandy sound. I am almost certain that the patches in 0.74-2 have introduced this.

Darwin's Arena was a relatively obscure shareware game, it's only claim to fame was that few shareware games supported Tandy graphics & sound. It was written in QuickBASIC using machine language Tandy support package called GRAFIX by Joe Albrecht.

This is mostly just a bug report.