/Newbie/ Simple SSM 2019 pre/ Distortion

Hi guys.
I fell a bit stupid right now - finally decided to make something myself, and started with (apparently not) the simplest thing on can imagine, a microphone pre based on opamp. Say, "$5 pre".

I'm powering it using 4x 9V batteries, so power supply shouldn't be and issue.
After assembling on a prototype board, i connected the microphone to the inputs, the output to the card, and - it's working. Great. But...

Microphone with sensitivity 2.3 mV / Pa distorts during speakiing with open gain loop (even though gain appears to be at unity).

I'm using the attached circuit though there is no phantom power, so i'm only using C4, R1 and R2.

During assembling I've connected some things totally backwards, it took me a while to figure it out - any chances I might have burned the chip?

This is totally my first try of DIY, so any help is greatly appreciated.
Krzysztof

EDIT: just found the reference input which sets the gain should have an impedance of 10k is open with the battery disconnected, and shorted when i turn it on. Sign of a broken amp?

When you say reference input do you mean pin 5? this should be connected to ground

With C4 R1 R2 it should work. Pin 5 connected to ground. Rg open circuit (no connection between pin 1 and 8) That should give unity gain

Pin 5 is grounded. I confused reference input with Rg - impedance between pins 1 and 8 is weird. (or should it be this way?)

This is the type of distortion i'm getting with input at 0.3V at unity gain...
Maybe i messed up something with power supply? I've connected + and - of 4 9V batteries in series to inputs 7 and 4.

You should connect the junction of the 2nd and 3rd battery to pin 5 (Ground).  This will give you +18 on pin 7 and -18 on pin 4.  right now you have 36 volts between 7 and 4 with no ground reference.

Works as a charm now.
Thanks for helping the beginner.

Glad to hear it!  We were all beginners once  ;D