No volume when video recording on Iphone 4.......

Had this happen to my phone just last and couldn't work out why the videos I'd recorded at a festival I went to weren't playing and it turns out I had dust in my microphone.
Brilliant advice helped me a lot, thankyou.

I had exact same problem.. What i just did was hold on power and home button until my iphone restarted...... Worked for me... :-)

I tried everything said on these posts and restarted. It works. So no matter what you do, remember to turn it on and off again, not kidding!

just change charging cabel ,

Maybe this will help. I logged into my iTunes where I listen to the radio and I had turned the volume on the iTunes radio all the way down. Turned it up and it worked like a champ.

Same problem here, only it was NO sound whatsoever in videos. Phoning and Voice Memos worked fine.

Finally fixed it by trying to FaceTime (to another device in the room, so feedback told me what was happening).

Covered each mic in turn with fingers - oddly enough the app seemed to start using the bottom mics but switched to the top mic when they were covered.

Quit, tried a video recording and the sound was back.

So for me anyway, the problem was software not dirt or hardware. Somehow the mic had been switched off by software.

Thanks!

THanks. it works now