Hi eikka272,
We see you're having some audio issues with your iPhone. To clarify, does this only happen in those third-party apps? If you take a video with the Camera app do you get the same result? Does restarting the device help at all? If you have any bluetooth peripherals connected you may want to try disconnecting them and trying again.
Also you'll want to be sure that your device is up-to-date. You can learn how to do that here: Update your iPhone, iPad, or iPod touch
We hope this helps you get started and look forward to hearing back from you.
Take care.