Seeme like the device 'forget' the notification tone set for the different apps; that's a device-wide issue as it happens to me for various apps concurrently.
If I set my email and WhatsApp and Hub email alerts tone to 'BBM' it will 'stick' for awhile and then either reset to the default tone or go silent completely.
I have a better solution. Stop using Vogue by Madonna for your notifications. :-)
Scroll up boss! Stock notifications are in use here.....besides, if anything I would probably go for Led Zeppelin, with all due respect to the lady....