Can I keep the phone's earpiece enabled, even when an audio jack is plugged in?

[AC Question]

LG G4, Android 5.1.
Basically, I want to plug in a headphone jack and want to phone to not turn off it's earpiece. Hence still be able to hear from the phone and talk while plugged in.
.
*more Info*
Phone got run over by a CAR...BUT STILL WORKS! except... cracked screen and during calls the screen turns OFF!!! I can't use the screen, I can't use the dial pad, can't hangup, can't use other apps. The person on the other side has to hangup. Tried a lot things in settings but no luck. Thought it was the proximity sensor but proximity sensor works fine when I call my voice mail box: screen stays ON when help down and turns OFF when put next to my face. I found a hack, when connected to an audio device the screen doesn't do this, it acts normal. I can't always have a long wire plugged in and a Bluetooth headset drains CRAZY battery. I have a dummy audio jack: just the jack with no actual device on the other end. THE PHONE STAYS ON WITH IT! ...but I cant talk or hear anything because my phone turns OFF its own audio output when a jack is connected. Any suggestions and advice will be very appreciated.
THANK YOU!

 

[gavo360]

app called soundabout might work well for you. I had a phone that had a fault on the headphone port and it always thought they were headphones plugged in so automatically disabled the earpiece and main speaker but soundabout app has quite a few options so was able to bypass the headphone jack and send sound to the other speakers.