cc1190 TX power?

We have developed RF modules relying sull'evaluation board CC1101 - CC1190EM 869 MHz Currently we have developed a prototype consisting of 10 pieces contenetti the amp chip CC1101 and CC1190 . All the tests have had a very positive result , we now have a pre- made ​​of 70 pieces, but with some problems in transmission power out . In particular, some modules have a power of 50mW to others who are around that translated to 300mW 17dBm against 24.7 dBm are about all this at the same injected signal to the amplifier input . The circuit is the same dell'evaluation ( CC1101 - CC1190EM 869 MHz) , we measured the typical impedance at the frequency of transmission , we compared the filter out low in low compared to that dell'evaluation and there are no particular differences .... (if not null ) . We have imported files directly from your PCB documentation and the position and size of the components are perfectly identical. From datasheetil CHIP CC1190 should boost 20db and in fact most of the pre-series came around that power (about 50 sheets 19.5 - 21dBm ) , but 15 have a very minimal power ( 17dBm ) and the remaining has a power too high ... . Measurements performed in a laboratory with RF Rohde & Schwarz instruments calibrated We want to understand if the chip has some differences as high as that seen datasheet is reported only the typical amplification , but not the lowest nor the highest . I await response thank you very much !