Rocksmith2014 Break after Update? This should fix it. on steam
Go to the game settings > properties
Choose the Betas tab
In the text field under "Enter beta access code to unlock private betas" copy and paste the text below and hit the check code button
Then choose the legacy version which should be a big blue button/link labeled as such.
This will revert the game back to before the most recent update and it should work
after doing that mine works very well all my cdlc works I made a copy after that just in case