It's worthy to mention that I checked all sounds that resides in iPad: alert tones from 'ALERT' to 'UPDATE' and ringtones from 'MARIMBA' to 'XYLOPHONE' and none of them sounds like "susuu" sound. So.., where this comes from??
Mine seems to be generated by Simms Freeplay. I set a simm growing some veg and closed the smart cover, and hey presto "susuu" . Opened the smart cover and there was my veg!!!! Repeated it three times and got the same results.
I believe that the sound is combining from new email received on the XFINITY App. I plan on deleting the APP to see if it continues.
I believe that the sound is combining from new email received on the XFINITY App. I plan on deleting the APP to see if it continues.
Update- Since I deleted the Xfinity APP, I no longer get the "Strange Alert".
I doubt it is what you are hearing, but try turning the Lock Sounds off then on to see what it sounds like.