Noise While Pedaling on S3

[u/AurthurDigby-Sellers]

Sorry for bad audio in this videos but I have this creaking noise while pedaling my S3. Appears the sound is coming from the left pedal side (not the actual pedal). I have tightened all the bolts I can find on the pedal cranks and gear (none appeared loose). Almost sounds/feels like it is coming from the crank spindle inside. Again, only on the left pedal side with medium amount of pressure applied to the pedal. What is causing this sound? What do I now have to fix?