IOS 7.0.3 - Sound has stopped working on iPhone 4s

You don't happen to see a little quarter-moon icon in the top status area, do you?

By restarting, do you mean turning it off and then back on normally, or holding down on the power and home buttons simultaneously? I had that exact audio issue for the past few days, and have scoured countless forums with people who had the exact same issue. My sound hasn't been completely gone- notification sounds have worked fine. The problem comes with music and videos. It wasn't constant either- occasionally, it worked. But now my problem seems to have finally been solved! I held down the power and home buttons at the same time until my phone shut off, and then I turned it back on normally. ALL audio came back, and has been back, for the majority of the day- the longest I've had it back since the problem first started. Like I said, I was kind of confused as to what you've already tried. But, if you haven't done this yet, I'd definitely give it a go! I'm hoping if the sound fails again, I'll be able to "reset" it like I just did earlier, and have the sound return. Yeah it's a pain, but I'm finding more quirks and pains with ios 7 the longer I have it, so at least it's something 😝

My wife and I are having the same problem on both of our iPhone 5's.

It's evidently a new bug with 7.0.3

We don't even get ring tones.

I had this problem since the 7.0.3 update. I searched everywhere and nothing, the solutions gived were not working in my case. So, i did a lot of tests and tried everything. One single trick seemed to be working, but it's not a permanent solution, unfortunately.

1. You must go and deactivate Siri.

2. Restart the iPhone / iPad.

3. After restart, go and activate Siri.

4. Lock the iPhone / iPad.

5. Bring Siri and ask her / him a question (if you are hearing the "beep" from Siri and it will answer to you, you are good, if not, try to repet the process again).

⚠ Again, this is not a permanent solution, sometimes lasts 3 days, sometimes one day.

I do not know yet why is this happening, but it's not related to applications (in my case).

Waiting for the next update to resolve this.

I have sound issues and the little moon icon, what does it mean?

It means that you activate "Do not disturb". Go in Settings > Do not disturb > and turn off ( Manual & Scheduled )

And the easiest method is swipe from bottom to see Control Center and tap the moon icon, see below.

Keep me posted and if my answer helped you please add.