Cannot work out to stop Line calls automatically turning on my speakerphone,  I'm lost for an answer.

 

Any advice much appreciated.

 

Thanks. 

Here are some solutions suggested from another forum, for whatever it's worth...

 

1. Does Driver Mode automatically turn on speakerphone, perhaps? If so, turn off Driver Mode.
2. Also check your status of Setting-> Call Settings -> VoiceMail -> Speakerphone.
3. I had this happen to me before and I found that it was due to a third party power cable that I was using to charge my phone. Somehow, the phone thought I was in driving mode as a result, and I couldn't get out of it. 
4. I had the same problem and finally found out that the speaker phone option was to do with the GPS settings. Unknowingly I turned it off and closed the app and voila! The problem was solved
5. The same thing happen to my mums phone I took the battery out for about 10 seconds and put it back in and it work
6. What worked for me was going to Settings - > Language and input - > read notifications aloud. There I turned off settings to read notifications. While we shouldn't have to do this, it worked for me.
7. http://www.wikihow.com/Turn-off-Speakerphone

If you have "Ok Google" activated please try to turn that off and see if it fixes your problem.