Hi Friend,
First, try to find the solution by going to Settings >> Notifications and then tap on Messages, then you can set to have the sounds back.
Try to use the volume buttons to adjust it. Go to Settings>>Sounds, and check if Adjust Volume with buttons is turned on.
Check in Settings>>General>>Restrictions if there is a restriction for volume turned on. If yes, turn it off and set the volume limit as higher as possible.
About text tones, go to Notifications Center and turn Sound on for Messages
Go to Settings>> Music and check if Volum Limit is set for Maximum (the bar is completly in blue), and Sound Verification is Turned off.
Go to Settings >> Sounds and turn Adjust with Buttons on. In Message sound, be sure you set a standard Apple ringtone. Tap it again to listen the ringtone ringing. If not ring, well, your speaker probably has a problem.
The speaker is easy to break if wet, even wet for a little. My girlfriend's iPhone speaker broke with some drops of a drink.
Anyway, check if Restrictions is turned on, reboot your idevice, be sure you have selected a pernonalized sound (ringtone) that works (change to a standard ringtone), check if "Do Not Disturb" is turned off.
Hope it helps
