There’s no need to add video to the menu unless you want it…just add the audio to a still menu. Also, you’d need multiple menus- one for each audio file you want to play- and link them together in all the menu buttons.
Higher burn speeds are more prone to write errors. For the least chance of burning errors, burn at the lowest speed available.
I’ve not heard of the Sonic brand of DVD media, so I don’t have any idea of its quality level. Some well regarded brands are Taiyo Yuden, Verbatim, and TDK. You can find out more about DVD media quality by researching user reports at https://www.videohelp.com.
Ooh..this sounds like either poor quality media, too high burner speed, or a burner problem. My guess is one of the first two. Which brand of DVD media are you using, and what type (DVD-R or DVD+R), and at what speed are you burning it?