Hi @mw, I wonder if you are hitting the issue that the regular .SSS milliseconds mask doesn’t play nicely if the milliseconds comes in as only one or two digits, which they might sometimes do.
If you keep the milliseconds but change them in the time part of the format mask from
HH:mm[:ss[.SSS]]
to
HH:mm[:ss[.SSS][.SS][.S]]
I suspect the occasional break might go away as it will then handle all formats of milliseconds.
Just a thought. 