Binding support for Yamaha TSR400 - identical to RX-V4A

I own a Yamaha TSR-400 which is identical to a RX-V4A. The receiver is discovered but thing initialization fails. I assume that as a RX-V4A it would be supported, so maybe it is just a matter of treating the TSR-400 as if it was a RX-V4A model.

Any advice where to start in the binding source code?

Thank you