HK Onyx Studio 4 bluetooth speaker
I found a solution for the pairing problem between the speaker and a Macbook pro running Monterey 12.6.1. I could get my MacBook to pair with the speaker but then it would not show up in the volume control to be able to send the sound signal to the speaker. I discovered that if your iPhone or another device is also paired with the speaker, the MacBook will not take control of the speaker and use it as an external speaker. The simple solution I found, turn off pairing with all other devices and everything went back to working perfectly between the MacBook and speaker.