The line switcher is for running a mic through everything for looping things. Currently have to get a new cable for that so until then its just bass going in.
The boss lmb-3 is literally just being used as a volume reducer. I have my amp dimed and then use this to bring it to normal levels. When I need air pushed for solos, I turn off the boss.
Or I could just use it as a boost but fuck that.
