I know this has been discussed in many subjects but here we're talking about the IR blaster, the one that controls other IR devices (TV, amps, etc.).

I have the Shield TV Pro 2017 model for a week now and I'm trying to put my TV and my Marantz amp on sleep mode when I put my Shield TV on sleep mode (and also wake them when I woke my box). After many tries, I think that the IR commands doesn't come from the box but from the controller (not the remote) itself ! So that if the controller is not in front of the devices, the commands aren't captured by them.

Am I right ? Do I miss something here, like an option to switch from controller's IR blaster to box's ?

Thanks in advance for your help and maybe tips & tricks around that useful feature :)