W210 E55 misfire at high RPM

[Austin814]

I have a 2002 E55 with 49K miles. I have twice now had a misfire on cyl 6, once in May (reset thinking it could have been a fluke) and now again 4 months later. Both times the misfire happened at high RPM (100MPH+) and both times on Cyl 6. After the misfire the engine runs rough until restarted. I have read through the misfire posts and nothing refers to it happening at high RPM and I thought that might help in narrowing down if it is the plugs,wire,coil or other? Any thoughts?

The MAF sensor is 8 months old and is OE Bosch
The Crank Position Sensor is 3 months old (suggested by dealer when in for service)