not really enough information for an answer but try this:

initialise the 7k.
save a normal performance save in a temp file.
press and hold panel set, confirm in expand with page 2 mic set to off.
press customise, data protection, set mic to on and ok in the screen.
press and hold mic and confirm the default of room, 99, 100, this is what is saved and will be loaded from your temp file.

change to karaoke, 30, 20.

press load, temp file, page 2, set effect memory to no, and load.
press and hold mic - settings remain and have not changed to those in the loaded file.