Incoming mail notifications not working on Samsung Galaxy S4

[beh]

Neither the vibration nor sound notifications for incoming emails is working even though they are set. Similar settings in my S3 work fine. Am I missing something here or is there an issue? Thanks in advance for your assistance.
Bruce

Update:
I realized upon further research that AquaMail is using the "system" sound for notification of new mail instead of the "notifications" sound. Since I don't use sound for key strokes and the like "system sounds" I have it turned off.
Since the Galaxy S4 has separate settings for "system" and "notifications" sounds I would request that the option to have AquaMail set to look for one or the other as appropriate be incorporated in an upcoming update. Thanks,
Bruce

[Kostya Vasilyev]

The sound preference is a stock Android "sound picking preference" and whatever list it comes up with is determined by the firmware and whatever is installed on the device.

I'm attaching a couple of screenshots from my Galaxy Nexus - you can see that some apps can get into the list when picking a sound, in this case, it's Solid Explorer.

As for the sound type, it definitely is set inside the XML file as android:ringtoneType="notification"

[beh]

The sound preference is a stock Android "sound picking preference" and whatever list it comes up with is determined by the firmware and whatever is installed on the device.

I'm attaching a couple of screenshots from my Galaxy Nexus - you can see that some apps can get into the list when picking a sound, in this case, it's Solid Explorer.

As for the sound type, it definitely is set inside the XML file as android:ringtoneType="notification"

Kostya,
Thank you. Your explanation and the screen shots allowed me to figure out the issue I have. I had picked a sound in the phone's notifications section that is not on the AquaMail notifications sound list. Now I have them in sync so things should work. Thanks again.
Bruce