As I figured and many did, "listen for ...hours" would not help the main issue.
The low price tag perhaps made manufacturer(or dealer) be negligent to details and quality of assembly and setup.
If you have tiny pliers something like in Leatherman pocket tool I'd carefully remove all cartridge clips and crimp them slightly more to make sure that they provide nice and tight connection to the cartridge pins. Be super careful not to rip them off the headshell and always use pliers when taking off and fitting back on. I'd also check carefully alignment and properly set-up VTF with tools to check and fix manufacturer or dealer negligent setup. If you go to turntablebasics.com, you'll be able to find basic tools to properly align cartridge and tracking weight. With new wires I'd work on research first. I don't know any market for outboard interconnects with thin gauge for turntable. Basically you'd want the same thickness of wires as going out from your arm on the interconnects. You'd also want minimal per-unit capacitance of wire, because for the MM cartridge it's crucial and not so for MC. For your reference, find out the electrical parameters of the stock interconnects you're using from manufacturer.
Years back they used to be available in conventional electronic stores with ground wire attached, now I've seen some on internet (needledoctor) at price tag 4x higher than your whole analogue setup. If you don't want to tense your wallet and save a lot without loosing performance of your system, I use
http://www.gepco.com/products/proav_cable/analog_audio/singdual_xband_F.htm. This cable is easy to fit safely onto the RCA jacks and provides low-to-no noise signal transfer with great dynamics. I'm sure that it will outperform your stock interconnects if properly terminated. For best results use
http://www.parts-express.com/neutrik-nf2c-b-2-profi-professional-rca-plug-pair--092-114 Neutrik Pro-Fi connectors that are very easy to terminate and lockable.
