Since the update i did yesterday I've been having problems with the speakers, they just don't work, I have sound with the headphones but the speakers don't work, don't even the phone calls and apps sounds :/
i have a lumia 720 with cyan, but since an hour ago it's working fine, really weird, today i couldn't answer like 10 phone calls because of this problem
Have you tried just powering the phone off and back on? Occasionally, my headphone jack would lose the left channel. Resetting the phone fixed that issue.