if i enable in audio common edit effect the mfx then sound come back in headphone but why before all the bank were sounding
and now i have to enable the MFX for it sound. i never did any programmation on these patches, i left them
as it was . but again why headphone ????

Sorry, but it is impossible for anyone to help you sort out changes you may have or may not have made to your instrument. There is certainly no difference between the information at the Main L&R Outputs and the Headphones jack... The signal should be be the identical signal - at all times.

Some of what you conclude has no basis in fact. You were experimenting and have either forgotten what you've setup and are experiencing your own self made "bad audio loop". This is usually not a fatal, you may just need to reset things. If it consistently doing the same thing and no one else seems to be getting the same result as you, that maybe a good thing - because consistent means it's just one thing to fix, in all likelihood.

What you can do is reset your instrument.

NOTICE
When the Initialize operation is executed, all target data and system settings you created will be erased. Make sure you are not overwriting any important data. Be sure to save all important data to your USB flash memory device before executing this procedure.

Go to [UTILITY]
Touch "Settings" > "System"

You can initialize Utilty Settings, you can initialize User bank data, or you can initialize both Utility and User settings.

i will do the reset as last chance . but to be logical as there are no parameters to set headphone it can't be this type of issue but there it is ! this is a ghost in the machine, let'see if the exorcism as you advise works. thanks.

the fact that the level of the virgin converted can finally find their way thru the master effect compressors to the headphone point maybe something that is egnima for me.

the reset of montage OS did the trick the ghost vanished