Unable to Start MULTI-engine aircraft

I've been 'simming' for decades.  This recently started and I'm not sure where to look for a solution.
A handful of months ago I purchased new Throttle Quad (4) engine, and a Yoke.   No problem for several months.  Lately, I attempt to start my Lockheed C-121 (or any other multi) using new engine start assignments (FS2004). e.g., press #3 to start 3.  Press #4 to start 4, etc...  #3 will start but i can't get the rest to start.  I've been thru every detail and checklist item on the Connie to see What is Not turned on, and crosscheck where my engine levers are set.  I resorted to Ctrl-E.  That will turn the engines but not long enough to fire up.  My only current solution is to select a single engine a/c (C-172) - start its engine. go back to the Connie - and all 4 engines are running.  It may be that I shouldn't be using the #'s 1,2,3,4 to start engines.  Perhaps CTRL-1,2,etc would be better.   Thanks for any input.