HEOS amp input switching

I just recently started to use HA and I am amazed by the features already and first wanted to tell my thanks for all works put into it.
I am having a HEOS enabled network player and so far things work nicely. There seems only to be one feature that is not integrated yet (or I am too dumb to find it) which is AMP input channel switching. I guess most people have fully integrated HEOS devices, then this is not an issue. However, with separated HEOS devices and compatible AMP, one is able to switch the input channel of the AMP. The relevant section seems to be “4.4.9 Play Input source”:

Would be really cool seeing this implemented, as one would be able to switch input to TV, if a video is started, or switch to the network player, if there is something to play. As it seems only to be an missing API wrapper to me, I suppose there should not be too much of work required to get this implemented, but please let me know, if this is not the case.