Spurious tones working at 420MHZ in AD9363

Hello. Im using a Pluto board using AD9363. We are using the loopback mode (RF RX > RF TX) and inyecting a tone in 420MHz. Using the original firmware v31, no custom.

LO: 420MHz

So we have a 60db diference between the spurious tone and the main tone. This is okay ? 

Also i do a test with the same firmware and Loopback on (Digital TX > Digital RX) , but using the BIST mode (echo 1 0 6 0 > bist_tone) and i have the same spurious:

Also the spurious tones were generated without any signal injected, just in loopback.

add info
[edited by: FCAG_123 at 4:21 PM (GMT 0) on 23 Jun 2020]