Envision Yoga uses audio that alternates between your left ear and your right. That back-and-forth is the engine of the whole practice, and it only works in stereo. Phone speakers and single earbuds flatten it into nothing, and you'd never know what you were missing.
Put on both earbuds or headphones, then press play. You'll hear a soft tone on your left, then on your right.
Did the sound move from one ear to the other?
You're set.
Your setup carries the practice properly. See you on the mat.
Let's fix that. In order of likelihood:
1. Both earbuds in? One earbud gives you half the practice, which is none of it.
2. Playing from a speaker? Phone and laptop speakers blend the two sides together. Headphones or earbuds are the way.
3. Check your balance setting. On iPhone: Settings, Accessibility, Audio/Visual - make sure the balance slider is centered and "Mono Audio" is OFF. On Mac: System Settings, Sound, Output.
4. Bluetooth acting up? Reconnect your earbuds and try again.
Curious what the left-right audio actually does? The story is at Where This Comes From.