Share your experience!
I have this problem on Xperia XA Ultra, android 7.0.
Happend to me several times, all settings are correct, the alarm only vibratres and makes No sound, very annoying, No 3rd party apps used for alarm, sound management. I run the risk of waking up late for work everyday, this bug need to be fixed immediately.
Does this issue happen if you use a 3rd party clock and alarms app? I suggest you try Timely app for testing.
I tried Timely 3rd party alarm app as you suggested, same problem, Alarm makes No sound, vibrates only.
I am curious, when this problem will be fixed. Abviously sony software has a bug that needs to be patched in the next software update.
Well, i experienced this bug 2 days ago and i figured out that forcing stop the application solved the problem i went for settings>internal storage >apps>clock>clear the cache and data then force stop it,i tried the safe mode option and another clock apps and didn't help
@Messam2305wrote:I tried Timely 3rd party alarm app as you suggested, same problem, Alarm makes No sound, vibrates only.
I am curious, when this problem will be fixed. Abviously sony software has a bug that needs to be patched in the next software update.

I only made this account to let you know, 2 years later - same problem. Zero fix my friend . Nobody cares lol
I have the Alarm problem.