@breathlungs the amps are being pulled form your computer and not the MagSafe. Yes, you would need a new cable, no doubt about that, but you are having issues with your Magsafe. It's possible your computer is trying to pull to many amps causing possible overheating of an already "tired" MagSafe. The buzzing could originate form the coils, or the transformer in your power supply. I am not fond of the fix on your fuse, since hat will not protect your MagSafe and may actually lead to its demise.
Not sure what you have going on with your Trackpad but If I remember right you have the battery right under there. I think it's time to open your computer up and see what is going on with it a well.