[wc4482]

/autoinventory

Make a macro and bind it to a key (such as "x" or "z")

What it does is drop whatever is on your cursor to the first available slot (such as clicking on your class icon when you open inventory)

To switch from two weapons to an instrument... (assuming you have Vert UI or slots dragged to hotbars)

1) Click on your primary weapon
2) Click on the instrument in your inventory
3) Click on your secondary weapon
4) hit your /autoinventory key (Best practice: have an open bag slot so your secondary weapon doesn't get moved to a bag or worse the ground!)

From Instrument to two weapons you can either:

1) click your secondary weapon in your inventory
2) click your instrument in your secondary slot
3) click your primary weapon in your inventory and hit hotkey

OR

1) click secondary (instrument)
2) click your primary weapon in your inventory and hit hotkey
3) click secondary weapon and hit hotkey