Spike in current limiter
After my failed attempts in the comments, I point the finger to V1, who has (machine) zero internal resistance and is forced to deliver the charging current for the capacitors (through the other series resistances in the circuit). Normally, you'd have both a limited resistance from the input supply, and some capacitor at the input, so simulating that by adding Rser=1m Cpar=1m to V1, seems to solve it.