I don't stream the workouts. I'll search the workouts write down the exercises and then use my phone for music. It works for me because I have the same complaints.

You can play music with the app. Just start whatever music app you prefer to use before starting your exercise and the workout app will decrease your music for prompts on the next exercise. Hope this helps.

To the left of the workout there is a picture of a speaker. Click on it and you are given  two volume choices.  One is for your phone volume which you can control the signs of your music (the bottom one). The top one you can control the volume of the video. I set the video volume a little louder than the music.