Thank you for the reply but I have already figured out that it has an auto-off feature. It was never mentioned in the instruction manual nor in any description of the speaker before I bought it though. I have the original Soundcore which does not have this feature and I am very satisfied with that one and is one of the major reasons I decided to get this Soundcore Boost one as well.
But as I mentioned, it turns off only after about 2-3 minutes of no audio signal input. Not 30 minutes. And since it is connected by AUX cable to my TV, it is never disconnected from the host source.
So now that you have told me all this, then the only conclusion is that the unit I have is defective, correct?