Thanks for the advice which is greatly appreciated.
I hope it is the same when working with a Lectrosonics SRA receiver too. I have set the gain in the receiver to zero dB, and the channel 3 & 4 recorder gain to +5dB, as you have suggested.
Now, I If I am to connect a shotgun microphone like an MKH 416 running on external +48V phantom power, will the +5db setting will be adequate or would I need to increase it?