So I bought a Marshall CODE 50 a bit ago, and with nearly device I've tried - there seems to be a lot of issues with getting the gateway app to connect to the amplifier in general (most of the time it doesn't work - despite pairing just fine).
I've tried this on the Samsung Galaxy S8, iPad 5th generation, iPhone 7+ - The connection issues seem to stem from the apps use of Btle on these devices.
To experiment, I built an application that connects to the amplifier via bluetooth for Windows, and issues commands to the amplifier through the PC. This application uses a "classic" (SPP /RFCOMM) socket connection to send commands. The application works perfectly fine via this means - it can be seen running below:
As an experiment - is there a way to force the mobile applications (if it isn't using a btclassic / rfcomm connection) to use a btclassic connection as opposed to btle?
Thanks and all the best,
Principle Engineer, Pulse Interactive
Lead Software Engineer, Pirahna Bytes RED