cranks slow over first cylinder

[barf]

'09 ProStar CM871.

This just started yesterday. My engine is scaring me, I thought it wasn't going to start. It was off for about 1 hour. I went to start it and it started to crank very slow over one cylinder, then faster over the next 3 or 4 then fired up. It has done this a few times since, and a few times started normal.

Is this possibly a hydro lock situation?

I had the starter replaced a couple months ago. Volts reads 12.4 after truck has been off for an hour. Engine sounds normal once running.