Mine would do that too if the engine sat for a few weeks without startup. I now turn the motor over for 5 seconds or so then stop, then pump the gas and hit the starter again with no noise.
It was worse when I used 15w-40 and 10w-30 oil. Now I use 5w-30 (full synth) + the 5 second prime and it no longer has the noise after a long period of no starts.