When using my iPhone I get an echo of my own voice

Hello SALOS Dave,

If you are hearing an echo in your voice, whether through internal speaker or headphones, it sounds like the issue may be with your microphone. Take a look at the troubleshooting steps for the hardware of your iPhone in the resources below:

Get help with hardware features on your iPhone, iPad, and iPod touch
https://support.apple.com/en-us/HT201401

First, make sure you're using the latest version of iOS. If you still have an issue after you update, find your symptom below and follow the link for help.

Acoustic-speaker/microphone/receiver

Get help with these issues:

• No sound or distorted sound from speaker
• Microphone issues
• Receiver issues
• No sound through stereo headset

Issue not solved

If you still have an issue with your device, contact Apple Support.

Last Modified: May 6, 2015

Get help with the microphones on your iPhone, iPad, and iPod touch
https://support.apple.com/en-us/HT203792

Test the microphones on your device

To find out if there’s an issue with the microphone on your device—and not an app that you're using or your cellular connection—test each microphone.

Microphone location can vary by device, refer to the technical specifications for your product.

iPhone

There is more than one microphone on your iPhone.

To test the primary microphone on the bottom of your iPhone, open Voice Memos and tap the record icon. Then speak into the microphone and tap the play icon to play back the recording. You should be able to hear your voice clearly.

If your voice sounds faint when you’re using the speakerphone on a phone call, make sure that your iPhone receiver isn’t blocked or covered.

If audio from video recordings sounds faint, or Siri can’t hear you, make sure that the microphone near the iSight camera—on the top, back corner of your iPhone—and the receiver isn’t blocked or covered.

Happy Holidays!