Ge w machine stops as soon as it goes to agitate cycle then finishes rest of washing

Hi
We’ll my issue is that my ge top loader, stops 20 seconds in to the wash cycle…then continues with the rest of the cycles…I’ve observed this and it does make a clunking noise as if it hits the side of the machine at the point of stoping…
I made an inquiry at the local appliance guy and he thinks it’s the belt…I seem to lean toward the suspension…and ideas before I dig in and play mr fix it…would be greatly appreciated
Thanks
Mpep60