LM386 not passing white noise signal that was generated by a second LM386 (updated)
Pin 3 (final stage) might need a resistor to ground - try 1kohm. All the application circuits I've seen do have a lowish value.

Also I have reservations about it working correctly without a low impedance on the 1st stage speaker output (after the capacitor) so try a resistor on pin 3 (2nd stage) that is more like 10 ohms.