My car keeps dying with a new battery - could it be the alternator?

Thanks for the suggestions. I typically drive about 30-40min to work each day and live in NC so the weather isn’t bad. I do have subs hooked up which I had installed when i got the car. Could something with these have gone wrong? I will be sure to get the alternator, drive belt, and main power cables looked at. I’ll also have them do a parasitic load test.
Thanks