What you're seeing is called CEC (Consumer Electronics Control). The article below goes over what exactly this is and what it is called within some different devices.
Each of the devices have a different area to turn this on or off, so you may have to reach out to the TV Manufacturer for the exact spot, but it should just be within the TV Settings.
I hope this helps!!
I have recently attached a Humax DTR1000 YouView box to my existing Slingbox Pro-HD, and all initially seemed to work extremely well.
However, I have discovered that when I power up the video source (the Humax box) remotely, it also turns on the TV. As this arrangement is to be used by someone connecting remotely, in a different time zone, as things stand, they will turn on the Humax box when they want to watch (our time very late evening/overnight) and the TV at home will start, which has the potential to disrupt my sleep, but also just isn't what I want to happen.
Does anyone have any clues how I can remedy this?
Thanks in anticipation.