Sota reflex clamp problems

I recently sent my reflex camp back to Sota for repair. They rebuilt it , I was then able to pick up my 10 lb platter with just the clamp whereas before I could not. After 2 wks of use the clamp tension appeared to be less than after repair. I had to remove my platter this weekend and when I tried to lift it with just the clamp as Sota claims you can do , the clamp slipped. No damage to platter as I caught it w/my hands.
Has any body found this clamp to be less than satisfactory/had similar problems?
Are there other clamps that can be used on Sota tables that clearly work better?
I am not interested in upgrading to vacuum system.
I had a Sota turntable briefly (vacuum Star) with a Reflex clamp. When I received the table the clamp did not function properly. If you look inside underneath the clamp you'll see a plastic(?) allen wrench screw which is adjustable and apparently adjusts the tension or amount of clamping force. I adjusted it and my clamp worked fine.
just like pug said ,take right size allen wrench & adjust the tesion every once in a while.(just not too tight)
On early SOTA reflex clamps there is a screw that is accessible from the bottom.It's reccessed at the center where the clamp fits over the spindle. You can turn this brass screw to increase or decrease the tension but you have to hold the center plastic assembly in place with a small flat screwdriver so that it doesn't slip when you turn the screw.
Hope this helps.