Shorting pins for balanced input?

My question is two fold. I have a BEZ Q3b preamp with balanced and rca outs. I use a Rawson alpeh J clone which also have balanced and rca ins. Recently I noticed a slight gain drop and thought it might have something to do with the shorting pins Tim included with the amp. Do they have to be used a certain way--pin 1 to 2 or 2 to 3--? The other thing I did was change the 5z4 tube. I don't know what did the change but now the gain is back to normal. Go figure. Great combo but I would like to know what made the difference since I did both changes at the same time. My guess is the tube. Thanks and enjoy the music.
Why not use the balanced ins and outs?
I have used the balanced ins but wanted to know if there was a certain way the pins should be insetred when using the rcas. Probable a silly question but when you don't know you ask. Like I said all is well now.
Normally pins 1 and 3 are shorted.
When I had my old Krell Ksa-250 amp, if you used the single ended inputs, without inserting the shorting pins into the balanced would get Hummmmm with your music.

Never tried using the amp that way Sogood51. I'm leaning toward the balanced ins as far as sonics go. Using a pair of Kimber Hero ic's and like what I hear. Thanks for the replies Rwwear and Sogood51.