My daughter's Xbox One S powers up, makes the ding noise, but only shows a black screen.

Try holding the power button for ten seconds then restart it. If that dont work try checking the cord to the tv from the xbox unplug a replug it in.

the slim makes a ding noise when you power it up from the console or hit the eject button

My friend recently had this start happening, he turned it on for the first time in a while to install Advanced Warfare and was met with a clicking noise for s few min, he turned it off and waited a few min, when he turned it back on it will show the Xbox
boot logo and go straight to a black screen. He;s tried all every power down option and gets a black screen no matter what.

Is it making the "ding" noise when it does this? It might be an issue with the touch sensor on the power button. It'll be covered under warranty, so you'll probably want to get a repair set up.

Any noises that it would make should be a cause for concerb. The only noises Ive heard from my unit are the ding when I powered it down. I would keep monitoring the situation until it starts not doing things correctly. For now your good, but you might want
to invest in the 3 year warranty for $70.