This has happened one other time and I figured I had too much in my DLC file. I deleted some files and I didn't have any problems for a while until now. I can play a song and when I press enter to accept the "score" the game simply shows speaker stacks and locks up. I have to go to my task bar and close the program and restart to play another song, then the process repeats. 

 

I have also tried to replace the Avenged Sevenfold song "A little piece of heaven" and no matter how many times I delete and re-download the file it will not show in my DLC file.

 

Any suggestions for either issue?

I Cant answer to why this happens but I can tell you I have the same issue at times....It only happens with certain new (new to me added customs) but after I play them a couple of times and go through the hassle of restarting Rocksmith a few times after a play through of which ever custom Ive just added to my playlist it seems to straighten itself out and starts to work properly.