@crisch Hello,
Unfortunately, we were never able to reproduce this problem, nor do I have an idea what the cause could be. I assume it’s related to the Samsung firmware (as you can see, both devices are Samsung GT-I91*) which does something different than the default Android Contacts provider. Because Samsung’s firmware isn’t open source, there’s no reliable way to confirm that or find a workaround. The only thing that I can suggest is to use an open-source firmware (AOSP, CyanogenMod etc.)