Multitrack audio levels don't match waveform levels

Hello!
I'm working on a multitrack session and would go into waveform to clean up/normalize audio for each individual track. I'm normalizing all waveforms to -6dB. However, when I go back to multitrack, all levels are at -9dB. 

This didn't use to happen before. Is there a fix for this so that multitrack levels are syncing/matching waveform levels?

Thanks in advance!