Sorry to hear you're running into this frustrating issue with your Samsung Neo monitor.
From what you've described, it sounds like the monitor’s built-in Bluetooth audio is automatically trying to reconnect and take over your Bluetooth speaker when you interact with your PC.
TO better understand the issue can you confirm the exact model number of your deivce?
Is your monitor connected to a PC via HDMI or DisplayPort, and does it have any other devices connected?
When the speaker switches from your iPhone to the monitor, does the monitor show any Bluetooth-related popups or notifications?
