About a month ago I bought my K5 SV650S with 1,600 miles, in really good condition. Being a few years out of date I did regular maintenance like fluids, oil, etc., and of course a new battery. Its been my every day transportation since I bought it and I've noticed my gauges and headlights are progressively dimming. And when I turn the key on to let the fuel pump prime, it makes a deeper buzzing noise like the electrical system is being starved. Also, the bike struggles to turn over when I start it. Does it sound like a defective battery or something else?