Erratic spark advance under acceleration

[Gelf VXR]

I've been data logging recently and noticed some hesitation under acceleration most noticeably in fourth between 3000 and 4000 rpm, MAP > 95kPa. I thought maybe a spark plug misfire, no codes.

I found it in the log and spark advance is very erratic, I was logging retard due to knock which showed none, ill log total knock retard next time to see if its burst knock, I do have spark smoothing disabled also.