Quick Deep Blue Delay question

[Synsound]

I've built 3 DBD circuits and only one would go into self oscillation. I was curious why this may be. All 3 worked great but I want to be able to get into the weird. Would changing the value of the Repeat pot make a difference? If not, what might.
Thanks

[induction]

Reduce the 5k1 resistor that comes between the PT2399's output and input. Assuming you used the layout below, it's the only 5k1 on the board, and it's just to the right of the PT2399. You'll have to play with the value until you find what works best for you.

[Synsound]

Thank you.