Battery 3rd gen question

So I purchased a LI24FM Duracell Ultra Gold Flooded 725CCA BCI Group 24F Car and Truck Battery from batteries plus a little bit over 1 year ago . I am running a 300w amp off of it that’s powering my sub . The battery starting going bad just a little over. 1 year . My concern is that I might have an alternator issue or do u guys think it’s from the amplifier and the cheap battery . I got it replaced under warranty but if it happens again any recommendations? And the bracket in the middle that holds it had some battery corrosion on it ..

 

That’s a good battery I’ve had 2. Do you play your music with the engine off a lot, running the battery down?

 

Nope always with the truck running .one thing I forgot to mention was there was some battery corrosion build up on the bracket in the middle of it wonder maybe it was leaking ?