Q: sound error

Hello kirangeetala,

Thanks for using the Apple Support Communities!

I understand that you are not hearing sound from the speaker on your iPhone except for while on a call and in the sound settings. To begin troubleshooting this situation, I would recommend reading over and working through the suggested steps in the following article. Be sure to check the Ring/Silent switch as well as described in step 3. 

If you hear no sound or distorted sound from your iPhone, iPad, or iPod touch speaker - Apple Support

Have a great day!