I have one Bushnell and one Scout Guard. I don't have a concrete answer to provide, but after looking at a few thousand pics this year I do get the sense that some of the older deer are not comfortable in front of the camera. I will sometimes get 20+ pics in sequence from a doe or young buck, but rarely do we get more than one or two pics of a nice buck at a time and it seems like that they are more oftentimes looking right at the cam for at least one of the pics too.
My cams are silent, at least to my ears, and only have a blinking red light when they take their pic, no visible flash. For the most part we run those cams on mineral sites in the summer and up through the first part of October. I normally don't put cameras out much during the bow season and will put them back out in late December near food sources for a couple of months to see what the survivors are looking like.