T450s Intel Bluetooth issue - connected speaker, but no sound

[Pes5]

T450s uses Intel Bluetooth SW. Once connected to Bose Mini Soundlink, it generates no sound via that external speaker. I suspect a bug in Intel BT in my T450s. Other devices using BT connection (e.g., TP X230 with Broadcom Bluetooth SW, iPhones etc.) and identical Bose audio device work well. Any advice what to do? Thanks in advance!