How much does he weigh compared to the mice? If he's a year old and only getting mice, maybe is just overly food motivated? My little guy is about 6 months, 300g and eating 30 gram rat pups, that's about the size of a large mouse. So, if yours is larger, maybe increasing prey size will calm him down in a few weeks.
I am not sure how much the mice weigh and usually he is fed ASFs but I do not have any big enough for him at the moment... but my snake weighs in at 592g.