I could not hear the person I called unless I was on speaker. Also could only hear music on headphones , not on loud speaker.
My iPhone had got a little damp in the rain.
Solution was to connect my bike pump to the headphone socket with ball connector. A few puffs and all is now fine.
I had tried the usual suggestions to no avail.
I couldn't hear callers on my phone, especially if I was in a noisy place. I had the ringer volume on full so I thought it was a problem with my phone. My son has just told me what to do and I feel really silly - he rang me up and whilst he was on I turned the volume up using the side volume button. If this helps just one person I will feel much better - knowledge is a wonderful thing.
I went to make a phone call today and could suddenly could only barely hear the guy on the other side. The speaker phone worked fine. I powered down the phone and no luck with restarting it.
I remembered that it happened to my husbands phone a few years ago and I had read somewhere to blow into the space where you plug in the cable. Sometimes things get in there and touch the pins making the internal speaker turn off or down. I tried blowing in it and it worked!!! Everything is normal again.
Thank god because my phone is way out of any warranty and I don't feel like buying a new one!!