Lectro, B6 and COS11

Hi,

I have a B6 ("grey mark" output level) mic and use it with my 200D
systems.
I use the COS11 too with the 200s.
Normally, I need more gain (@ TX's input) for the B6 than I do for the
COS11 (COS11 usually around 10 or 11 o'clock, B6 never less than 1 or
2 o'clock)

So I'm surprised about the issue using the B6 with 400s
transmitters...!
Are you refering to higher output level B6?

Is there any issue using the COS11 (regular level) ?

And with a sensitive shotgun? (e.g. MKH60 while booming wireless)

Many thanks in advance,

Fernando