ST25RU3993 eval low output level

Hello,

I've observed that output level on both antenna port is lower than is specified in datasheet. I've checked it on two eval boards. Below results:

For internal PA: (output level set/ measured level/ detector voltage

1. -12 / 4,5 dBm / 0 ,71V
2. -6 / 8,9 dBm / 0,81V
3. 0 / 12,2 dBm /0,89V

For external PA:

1. -12 / 14,4 dBm , / 0,92V
2. -6 / 19,5 dBm / 1,05V
3. - 3 / 20,8 dBm / 1,08V
4. 0 / 21,5 dBm / 1,1V

In both cases output level is lower by 7-8 dBm that expected. Any suggestion?

Best Regards, Michał