Sorry to resurrect an old thread, but I have this EXACT problem on a TOTAN. Only my left 2 flashers on the playfield under the plastics, BELOW the left clear ramp are flashing once subtlety when SOME coils would fire. They are the only two of all the flashers that are doing this. they are doing it when the flippers are firing.
I will try to replace them back to incandescents and see if that fixes it