Need help with the TTL setup for Oly EM5 mk2 with dual ys-100a

I want to set up TTL for my camera but one of the strobe always seems not to work correctly (both fired but in the photo, it was dark on one side). I connect strobes to camera with fiber optic cables.

my setup was...

On camera : Flash mode - Fill in

Strobe : TTL, Slave ON, Light level - FULL

So what I did is that I changed Flash mode on my camera to manual 1/64. The strobes worked well (light in the photo is even on both sides) but they fired as strong as camera flash. I need to adjust strobe strenght by changing camera flash to 1/32 1/16 and so on... this is not real TTL anyway.

please help me how to get TTL for olympus em5 mk2 with dual ys-110a.

Thank you very much

You might try to cross-change the cables to see if one of them is responsible - I personally had severe TTL problems with my EM5 I and a YS110a until I changed from no-name to a genuine S&S fiber optic cable. From then on TTL was fine.

A dealer at the Boot exhibition told me that from customer feedback some Oly cams seem to be very sensitive concerning TTL. He said that in many cases the cables are responsible. On his advice I tried the S&S cable - et voila!