Is there a difference?
Manual on both says

Lo Gain +19 dBu 15 dB
But:
Connected to an AMS NEVE 1073 DPA the UFX+ red clipping led in TotalMix is totally en par with the LEDs on the Neve.
Where on the FF 802 FS, I can drive the input of the 1073 harder without clipping in TM.
I would rather like to have the inputs of the UFX + less sensitive like in the FF 802.
Could this be done with a firmware update?
Or is it just a different TotalMix behavior or different converters of the two interfaces?
Seems that even when the over LED in UFX Total Mix lights up, it is not sounding like converter clipping.