iPhone not playing music to JBL devices

Hello tastylighting,

To help troubleshoot, ensure the Bluetooth speaker is selected as the sound playback destination in Control Center on your iPhone. Although the accessory may be connected via Bluetooth, it's possible the iPhone is selected for the sound playback destination. Check out how to change the output here: Set up and use Bluetooth accessories on iPhone - Apple Support

"Play audio from iPhone on a Bluetooth audio device

1. On your iPhone, open an audio app, such as Music, then choose an item to play.
2. Tap , then choose your Bluetooth device.
3. While audio is playing, you can change the playback destination on the Lock Screen or in Control Center.

The playback destination returns to iPhone if you move the device out of Bluetooth range."

If the playback destination is set correctly, then wireless interference could be causing Bluetooth connection issues. Check out how to troubleshoot wireless interference here:

Resolve Wi-Fi and Bluetooth issues caused by wireless interference - Apple Support

Let us know if that helps.

Kind regards.