Support Repair N9320B, Amplitude Level measuaring is incorrect

[Thuyvv]

Hi All,
I have an errored unit N9320B, the Amplitude Level measuring is incorrect, the result measuring is larger than the RF level at the input ~ +6 ÷ +7 dB,
The monitor display ERROR 102. 50 MHz calibration reference unleveled when I Align all
Please see the video in this link and help us fix this error,

https://youtu.be/LjFS4vwu_VE
Thanks!