First my cdlc songs stopped working, I was getting stuck at the amp screen before a song. When i went to try and install the tool to fix it. It would let me start the installer for that. Ever since then i haven't even been able to boot the game. Anyone know any fixes for this?

It sounds like something got corrupted, is what I am reading.

First make a back up of all the cdlc so that they do not get deleted.

It is possible for whatever reason the D3DX9_42.dll became corrupted or is missing. Remove it from the folder if it is still there.

Try a file repair through verify files / from Steam library;

either right click the game in your Library, or click the gear icon from the game's Library page on the far right

From the drop down menu, select Properties, Select the Installed Files tab and click the Verify integrity of game files button.

Before attempting to run any cDLC make sure that the game works first.

If the game works after that then try adding the D3DX9_42.dll. Make sure that there is only one D3DX9_42.dll.

You may have to temporarily disable your antivirus in order to download the cDLC enabler. Remember to re-enable your antivirus after downloading. You may have to move the enabler to the Rocksmith folder that has Rocksmith2014.exe to run it. Most often you do not, but a couple people have said that they had to.

If that does not work, I personally would uninstall Rocksmith and re-install due to it sounding corrupted. Again, make sure you back up your cdlc before doing so. Again make sure the game works before adding the D3DX9_42.dll, and cdlc back to the dlc folder.