Thank you, Shannon!
Arduino Reference:
"A variable should be declared volatile whenever its value can be changed by something beyond the control of the code section in which it appears, such as a concurrently executing thread. In the Arduino, the only place that this is likely to occur is in sections of code associated with interrupts, called an interrupt service routine."
Spot-on, It solved the problem!
Code tags, is that what you get by formatting with </>, like:
volatile int Ticks; ?
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