N64 Audio Timing Issue

I'm not sure if this has been reported before (if it has, then you're welcome to close this issue) but music on the N64 core in Bizhawk experiences a desync in relation to the video. Usually this would go unnoticed as the music is often a background loop with no timing relevance.

The best example is to load up Super Smash Bros. (U) in Bizhawk and let it play the intro. After around 25 seconds, there is a section of the introduction where character names are listed and then short clips of them are show. When each name is displayed, there's an orchestral hit in the audio track. At first it aligns perfectly - but it gradually goes out of time (most noticably around Yoshi / Kirby). It gradually increases in this fashion as the intro goes on when compared to the console version. It's not game-exclusive, as the story to Banjo-Kazooie exhibits the same behavior, with the music beginning in time but by the end of the introduction things are happening several seconds earlier in the soundtrack when compared to the video.

It should be noted that the sound effects and any new sounds start in the correct place, it just seems that it's either a gradual desync in long-standing audio or it could be extra lag is generated by the core. I'm not sure the cause of this but after playing around with timing methods and settings to no avail, I thought it should be mentioned!

(author's username was @thecoreyburton)

Start by reproducing the audio/video drift in BizHawk's N64 core with Super Smash Bros. (U) or Banjo-Kazooie, using the intros described in the issue. Compare the timing against the console behavior and trace the N64 audio and video timing paths; done means long-running music remains synchronized with the video while sound effects still start correctly.