OpenSL ES on Android with SL_ANDROID_STREAM_VOICE. Microphone input is extremely low

Question

I use OpenSL ES and SL_ANDROID_STREAM_VOICE to route audio in my native Android application to the ear (telephone) speaker instead of the main speaker. The output to the ear loudspeaker is working fine, but now the audio input recording is very soft. Is there a way to enlarge or reconfigure the microphone in this situation? You can use the SDK or NDK through OpenSL ES.

Thanks!