I am having problems with my iPhone 6 64 gigs with T-Mobile.
Since yesterday, I have been having issues with the volume of the Voice Over sound effects and other sounds, but the Voice Over voice itself is low in volume, even though I have the volume of Voice Over on the rotor on 100%.
This seams to only happen when I have the phone on speaker, with headphones everything is fine.
Actually, is all of the sounds, not just the Voice Over sound effects.
I already did a reset of my settings, and the problem came back.
I tried to adjust the ringer and alerts, and the change with buttons on and off, and it seams to fix it, but when I need to raise or lower the volume, then the problem comes back.