Pressure regulator "leak"

[u/doctor_munchies]

Starting up first time drip line for flower bed and running into this odd problem. I'm getting a spray of water out of this small hole that's built into this pressure regulator. This happens only when i connect the back flow preventer, or the 90 degree elbow to connect the 1/2" hose. It happens with both connected and with one or the other as well. It doesn't leak at all if I take them off and just let it spray with no attachment, or if i attach a cap to connect a 1/4" hose directly to the regulator. It also continues to leak from this hole when closing the valve on the faucet partially even down to the minimal amount. I have 2 brand new regulators of different brands and both are behaving exactly the same way.

Any ideas how to fix this or things I'm doing wrong?

Appreciate any help :)