Engenius NMP-8602 Power Problems

Hi, i got some nmp 8602 cards, it worked fine the first days but sudenly they got down the power and now i compare it with a simple 17db card and have the same power (when i make a site survey and see the signal with my laptop),

I have changed all parameters (Power, country etc…) and always work with low power.only one of the 5 cards is still with high power

If any body can help me i will aprreciate..

Thnaks
Dimas