I have the same problem. I did however find a temporary solution. I tested and it works. See below.

Download an apk app called A2DP. Available on google search

Install it on your box. When you are loading the system before you click into mytv online click across to A2DP.

Click on it and click on Check Bluetooth A2DP. You will see 3 options AAC LDAC SBC. Click on SBC. It will say switch A2DP codec to SBC. Click yes.

Every time you turn on your bluetooth speaker you will have to follow these steps

The app is full of ads though.

I bought two Z10 PRO Max boxes at Christmas to replace a Z7 and Z8. I had bluetooth headphones that were paired to the z8 and work perfectly. These same headphones will pair to the Z10 Pro Max but the audio is cracking and cannot be used.

I reset, unpair and repair, same issue.

I heard multiple people complaining for this same issue on these Z10 Pro Max
Im am using Soundcore by Anker Life Q35 Multi Mode Active Noise Cancelling Headphones

Is there a resolution for this issue?