So in this thread, there have been many questions about the audio coming from MCU1 to MCU2. After my upgrade over a month ago, I was initially disappointed with the sound of MCU2. After a month of frustration in trying to tune the system but never getting it quite right, I decided to spend a day on an audio project and use a little science instead of just my ear. I mapped out the frequency response of the MCU2 audio and adjusted the limited EQ the software allows to obtain a much better sound.
If anyone has an interest, I created a new post with my results (and lots of pretty frequency analysis graphs).
MCU2 Upgrade Audio EQ Balancing - Coming From MCU1