Can you say that this is one of the two audio chip compatible??
AUD 305B 01213 1229B/I found this/…..AUD 305B 00054 1149A/this is the mainboard/
Samsung S6 sm-G920F no network problem solution:
When you face the problem not network found in Samsung S6, don’t worry apply reset method
but save your important data before reset the phone. After the reset your problem will be solved.
If problem not solve then use Second method, just open the phone and replace the highlighted components ….. more you can find here