Multitrack question

It's probably 3dB, not 2dB, but this depends upon the number you've got in the pan law setting...

If you go to Edit>Preferences>Multitrack and look at the first item, you get a choice of how the pan law works. If you you select the second option, this will drop the level of all inserted audio by the level in the box (usually -3dB). If you select the first (Left/Right Cut Logarithmic) mode, then there will be no drop of inserted level, and the pan control will work simply by dropping the level on the track you pan away from. Even though the pan situation only really applies to mono tracks in a stereo session, the only way to make it work realistically is to have this setting applied to all tracks, so that inserted levels remain the same whether the track is mono or stereo.

If you want a more detailed explanation of how this works with session files, then read the end of this thread:

Export stereo mix from a 5.1 session