For bluetooth devices with multipoint connections when it leaves the range of one of the devices it was connected to it will attempt to reconnect to the device for 10 minutes. During this time when it attempts to reconnect it will emit a beeping noise and will also cause bad connection while it is attempting to reconnect.
For this we recommend before leaving the range of one of the connected device to first disconnect it from the BTunes. This can be done by going into the bluetooth options of the device, look for BTunes and select disconnect. Now, walking out of the range of the device will not cause BTunes to attempt to reconnect.
Since the device is only disconnected and not unpaired when you return to the device you can select reconnect from the device's bluetooth options and it should reconnect to the BTunes. If the BTunes is turned on while the device's bluetooth is also on it should also reconnect automatically.