The microphone in my Aurora II (firmware build 0626) doesn't seem to work properly.
I've recorded this mp3 with Hi-Q MP3 Recorder speaking in my normal voice holding my tablet in ~7 cm distance with WiFi off and without microSD card:
I already tried alternative sound recording software the result is always the same and I'm starting to think that it's a hardware problem of my tablet.
Firmware update 0705 + Google Services Patch 0626 brought nothing.