KN5000/Microphone Problem

I have owned a KN5000 for about 3 years but have only just added a microphone. The problem is that I get a noisy 'hum' when the mike is plugged in through the keyboard.
The mike is a good quality Shure SM58, and another mike that I have reacts in the same way.
Any suggestions??

Hi Sharron
Could be that your microphone is High Impedence whereas it should be either low impedence or set to low impedence (bet I've spelt that wrong).
I've experienced this through working with a girl singer who uses a microphone standing right beside me...
Roger M

I'll say this gently, so as not to offend:
The mic input on the kn series is a joke. It's horrid, and should not be used by singers. Step away from the input !
Sorry - it HAD to be said again.

Mmmmm yes agreed
Rog

Before I got my KN7000 I used an SM58 with my KN5000 without experiencing any loud hum unless my mic levels were too high. I am only saying that,quality not withstanding,you should be able to use it with mediocre results at least.

Why on earth, would anyone want to hear their voice reproduced in a mediocre fashion? A better option is to buy a guitar processor, and plug a mic into the that, and then into the line inputs on the kn5000. Ignore the "mic" input alltogether. At least the tone will be acceptable, then.

I plug a HI Z mic into the balanced XLR on the rear panel of the KP-200S Stereo Motion Sound System. It is then assigned to both stereo channels as mono left and right. www.motion-sound.com
check it out
I love it.
Thanks to Dan01 for selling it to my wife Jann for my birthday. Thanks Jann
Bebop

Thankyou to everyone that replied to my mike into a KN5000 question. I shall investigate all options suggested. Sharron.