Max volume upon playback

[Indyajr]

I was using Spotify on an iPhone 5 to airplay to an Apple TV and had the volume set to max in the app in order to control volume from one device (receiver). Just a little while ago I plugged in my earphones and made sure volume was down to 1 bar using the iPhone volume control. I hit play in spotify and was welcomed to full volume through my earphones. This has happened several times already and I haven't started to cringe before hitting play or making sure I don't have the IEMs in my ears when first playing. Why isn't the volume syncing with the devices setting? This could either damage my not so cheap IEMs and or my hearing. Advice?

[Peter__]

When not playing, does the volume controls on iOS not control the ringer volume rather than app volume (which is an Apple design thing)?