Dual cam or single? Steel cables or synthetic? In either case, after 7 years it's time to replace the string. It could last 7 more years or it could break on the next shot. They creep (elongate) over time losing some of their strength.

And s mentioned, a good lube job wouldn't hurt.

I agree. You don't shoot much. I average about 300 shots a week and change strings at least every two years. Just a matter of safety.