Flash not synching on Minolta Autocord

Developed a roll of Portra 400 this morning which I shot out of a recently CLA'd Minolta Autocord. This is the second roll of film I have put through it, but the first time I've used a flash with this unit. First roll of film had no issues. On this second roll, first 8 shots were in daylight without flash; no issues. However, the last four I shot indoors with a flash (Metz 45 CL-4). I've used this same flash with another Autocord with no issues. But today, the last four frames that I shot with the flash produced no image whatsoever. I distinctly remember the flash firing on all four shots, which were at f/11 and 1/100th and the Metz flash set at that aperture too. I checked the camera, and the shutter appears to be operating as it should. I thought I had placed the flash synch switch on "X", but on checking the camera, it may have moved more towards the middle "F" (there are no 'clicks' between the "X", "F" and "M" on this unit). Could that be the cause of the issue?

Definitely…

If it wasn't set on X sync, you won't get any images.

You can check the x-sync by hooking up the flash, setting speed to 1/500, and opening the back to look through the lens at a light wall while firing the shutter. If it is synced, you'll see the bright dot of the flash in the lens.

Thanks for the responses.

I tried the technique described above. Very faint light, even when it is on "X" synch. Confirmed this with another camera that I know works, and easily saw the flash light through the lens when fired.

So... I guess maybe the problem lies within the switch?

Could be inside the shutter. Thee is a piece of spring brass that makes connection to a part tied to the shutter blades opening. This brass can be bent slightly to adjust the timing of its connection to match full blade opening.