CD74HC4046A: Jitter is showing up

Part Number: CD74HC4046A

The case:

Mount the PLL CD74HC4046A with one resistor R1, as example 14 Kohm, when a external sinewave signal is applied to pin 14 the PLL locks over a large frequency area without any disturbances.

I like to have a start frequency, to get this resistor R2 need to be placed and a signal with a frequency depending on the R2 value will appear without any input signal.

When a input signal on pin 14 is applied with a higher frequency then adjusted, heavy jitter will appear

What can I do to have a start frequency with locking for higher frequencies without the jitter?