Double event fire from wxTextCtrl

OK, this is rather simple, but can anyone tell me why this is happening??

I have reduced my app to a very simple case (attached). When run, and
the slider is dragged, page up/down, or line up/down, the text control
fires two events, even thought I am only calling SetValue() once! Why
is this??

My concern is, I am sending data serially to another device which
interrupts a process to accept the data. Currently, it is getting two
interrupts (the same value is sent twice) when it only needs to get one
- and is wasting processing time. Is there any way around this?

Any help is appreciated.

BTW, I am using wxPython 2.3.4.2

Thanks,
Mark.

test.py (3.76 KB)