OK, so this might not necessarily be an issue of the sounds coming from the speaker but more a matter of the sounds made by the audio chip itself -- the former being an external thing, the latter internal to your phone. If you look in your Settings >> Sounds menu, are there options to adjust different audio functions? Looking at my phone there are Media volume, Alarm volume, and Ring volume options. No clue as to what options Huawei includes in its Sound options but you should try messing with your menu options to get things working back to the way they were before.