Lots of knock - EGR CEL

[Sammy_Johns]

I am running a stock ASDU bin on a 7747 with SA and BPW hacks. Base timing is about 5* advanced. It recently started throwing a EGR Code and racking up the knock count. There's about 30 minutes of street and freeway driving in the log. I don't know if the numbers in the log are typical or show any issues. I intermittently have a vibration most noticeable at idle. Actually, I should say I intermittently have a very smooth running vehicle. Any suggestions of where to go from here would be appreciated.
I posted this too soon. Obviously, I need to troubleshoot my EGR system, then do some more data logging.

Thanks.