Why when Gameboy or NES games glitch, there is often a buzzing or “screeching” sound?

Question

I heard it was that it is trying to read non sound bytes as sound, but im not sure how accurate that is.

In: 4

Answer 1

The sound in old consoles is generally controlled by the CPU that’s also responsible for running all other code of the game. So if the game glitches then that effects that sound. In the best case the parallelisation of sound and game code remains intact and the sound plays as normal while the rest of the game glitches out. But often the sound computation is affected as well, and if it starts reading data that’s not intended for sound production then that’s for all intents and purposes random data. Random data results in white noise. Finally it’s also possible for the game to just not update the sound anymore, in which case you hear a constant tone.