How do I fix audio emulation on PCSX2?

My experience is mostly summed up by Mazura -- you keep trying one thing at a time until you see improvements -- but I have 2 things to add to that:

• This will be obvious to most people who have spent more than a few minutes tinkering with PCSX2's settings, but on Windows you can see the framerate displayed in the title bar of the game window. This is a handy approximation of how well the game is performing, and in my experience so far, audio performance problems are usually connected to video / general emulation performance problems, not isolated.
• If you have a modern gaming PC that is struggling with 12-year-old PS2 games, you likely have plenty computing power, it just isn't being allocated correctly. So there's a chance that a single counterintuitive setting will make a 500% difference in performance. This is what I found; I changed the VU0 setting to "Interpreter" and suddenly performance was perfectly smooth, even when I ramped up all of the graphics settings to near their max and switched to 4x native resolution.