I am suspicious of the 100K ohm resistor between the "vtune" test point and the varactor diode. That value may be too large. You might have to lower to 10K, or even 2.2K.
That resistor is used to pass DC tuning voltage to the diode (which changes capacitance vs applied DC voltage), but also serves to block the RF power from running down the line back to the PLL chip. But if there is any leakage current to ground, the PLL chip may not be able to overpower the high (100K) resistor value.
If you are looking for high quality audio, you MUST add a lowpass filter for the audio input. The lowpass filter must be sized to not let any audio frequencies above 15 KHz to get into the oscillator. This is because most FM radios (stereo ones) will flip out with higher audio frequencies, and fold them back onto the desired audio--causing severe distortion.
If you have any gear at all, test to see if the PLL is indeed working and locking the output frequency in a stable way to the desired channnel.