Rough engine sound at 30-60 mph on a 2012 Toyota Camry

I have a 2012 Camry, 4 cyl, whose engine has a random rough sound on a light acceleration, between 30 and 60 mph. It’s very brief, but seems to be getting worse and more frequent. It doesn’t happen when using cruise control or at speeds above 60. It is an automatic with manual option. I use a high grade gasoline and change the oil on it on a regular basis. Any ideas as to what this could possibly be?? I realize it could be a broad range of issues, but trying the process of elimination. Any help is greatly appreciated. Thanks