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I'm very new to this, so please don't flame.
I laid out this little amp circuit onto a PCB (all SM components), sent it off to JLCPCB and had 30 made. Out of those 30, 4 worked perfectly, the rest all fail. The working ones voltages are all correct as per the drawing.
The failed ones voltages all measured as per the parameters in red, and clip the top of the input immediately at the emitter of Q1. I've checked and double checked components and any differences between the good and bad boards, but can see nothing untoward.

The PCB's are flood-filled ground plane top and bottom. Could parasitic capacitances cause this problem? Why does a few boards work, but the rest fail?

Any help or insight is appreciated.