Strange Observation involving Pick Parameter in Amplifier Section

1Single-Coil, Pick Parameter = +2.5Glitches at sec. 4-6 and 8
2Humbucker, Pick Parameter = +2.5No glitches. Ignore accidental finger vibrato on start of note :-)
3Single-Coil again, Pick Parameter = +2.5Glitches at sec. 6-8
4Single-Coil, Pick Parameter = <0.0>No glitches