Alright, Thanks Aja for your reply - and everyone else too.
You prompted me to "play around" with it a bit more. I had already checked the mirror position - fine and mirror moved freely. I had checked the film compartment and hadn't found anything amiss. On your suggestion, I tried depressing the two buttons on the bottom plate - no difference.
I did notice that about every 8 or 10 attempts, it would fire, so I kept playing around. What I found was if, after the shutter fired, and I would advance to the next frame, if I allowed the advance lever to just snap back into position, the camera would fire again. If, however, I eased the lever back, as is my normal practice, the camera would not fire. I then played around with the double exposure lever and operated it a few times.
Now the camera is firing consistently again, even if I ease the lever back. Apparently, something had partially jammed the double exposure mechanism. No need to send it in for the present, unless this becomes an intermittent problem.
Very happy now, this has always been my favorite film camera - was my first serious camera many years ago. Not this particular camera - that was stolen, but one very similar. Would like to get one with the titanium shutter like my original, but this is close.
Thanks again everyone. Guess Oakland Photographic quality will remain a mystery for now, though I may try them in the future.