What if I installed Giphy but can't hear any sounds from them on my iPhone 6S?

You could, for decoration, but don't actually put them on the dogs. You might consider getting special collars that can act as substitutes for the rings.

Make it quieter. Muffle it. You can put something over it, or move the music source so the sound of the shower itself is a barrier between the music and...

It sounds like your microphone may be blocked. Ensure that your iPad case or other objects aren't covering it, and ensure that it's clean of debris.