problems tuning timing

Hi everyone,
I have an 03 tahoe flex fuel. I tuned the MAF, the VE table, leaned PE table a bit, removed some torque management settings. Truck noticeably lightened up especially at WOT.

However I have some issues tuning timing advance. I used the MBT table and compared with other tunes from the tune directory to build my high octane table. Problem is that I keep getting random KR while I log (around 1-3 degrees). Sometimes I get random knock while cruising, sometimes with sudden or light throttle acceleration and sometimes I do not get any at all ! I do not know if this is false knock or something. I disabled burst knock, and shortened the KR recovery rate to make sure I am logging any KR that occurs.

Here is my tune do you guys think my timing table is too aggressive :confused:

I am running on regular 87 octane gas

My suggestion would be to fill it up with 93 octane or higher and see if the knock goes away. Without looking at the tune I will say that it is most likely phantom knock if it's completely random.. If it is still unchanged with the better fuel then modify the knock sensor sensitivity a little at a time until it is gone.