I upgraded my iPhone 4s to iOS 7.1 and now the sound does not work and the volume controls do not work either any suggestions?

Try to reset the phone by holding the sleep and home button for about 10sec, until the Apple logo comes back again. You will not lose data by resetting, but it can cure some glitches after installing new software.

If this does not bring your volume control back, set it up as new device:

How to back up your data and set up as a new device

i am facing the same issue. Tried reset and even fresh install. Is this an OS issue or hardware issue?

I have the same issue after upgrade to ios 7.1. Tried both reset by holding the sleep and home buttons pressed, and restoring the device but the problem is still there.

Por aqui el Problema Mismo, Yo Tengo el Iphone 4 y al actualizar a la 7.1 estoy sin sonido y sin posibilidad de realizar llamadas. He probado a restaurar y a poner una nueva copia de seguridad, pero sigue estando ahi el problema.

I have the same issue after upgrade to ios 7.1.

I did restore to new phone myself but it did not solve my problem. Had to take my phone to the apple service. They did a fresh install and everything seems to be ok now.

After it was fixed , i did a restore from back up to get my stuff back on the phone

I would suggest that try taking your phone to apple service.