Sound speaker problem after connect bluetooth device

I am having problems with my sound on NixOS+KDE+Pipewire on my Lenovo Legion Pro 7 Laptop (model 16IRX9H).

When I log in with my Bluetooth disabled, the sound from the speaker works. However, when I enable Bluetooth, I can’t switch back to the speaker sound, even when selecting the previous device.

What could it be?

UPDATE: Even with the Bluetooth OFF, the sound works just for some minutes.

Related: Legion 16irx8h Speaker Issue · Issue #1039 · NixOS/nixos-hardware · GitHub

I found a solution here: