I just received a Mamiya C330 I ordered. I have a C220 and wanted to upgrade. I was looking forward to the upgraded film winding and shutter cocking a C330 would give me. I swapped my 80/f2.8 lens over to the C330 and loaded up a test roll of 120. Everything runs smooth other than the shutter cocking arm will not cock the shutter. The shutter cocking mechanism falls just short of enough travel to cock the lens. If I manually cock the shutter, camera fires and winds fine however, it continually will not cock the shutter. Any thoughts before I send this back? It was on a popular seller's website listed in 'Good' condition.