Remove the front panel of the washer.
Check the damper pads are not worn out.
The damper pads are felt pads that allow the transmission to move freely on the base.
This should be free of dirt.
Here is a link to your washer model A590.
Here are the damper pads.  | 
Washing Machine Repair 
SERIOUS VIBRATION IN SPINNING CYCLE. NEED HELP/ADVICE REGARDING BALANCE. MACHINE SHOWS LEVEL BUT EXCESSIVE VIBRATION IN SPIN CYCLE.
