Hi there. I have a problem that I just can’t solve. When listening to my projects through my headphones, the sound is distorted and full of noise. It’s not a latency problem. When listening through speakers, it sounds good without any problems. The headphones sound good when listening to something else, Spotify, for example. It must be something within my Cubase Elements 12.
Can anyone help?
What type of headphones?
Are they connected to the same audio device as your speakers? What is the audio device?
When you say “distorted”, does it sound like clipping? Is it very loud, very quiet, or normal volume?
Headphones are DT 770 PRO and they are connected to the same audio device which is a Focusrite Scartlett Solo.
There is no clipping whatsoever, it’s kind of the same “distortion” as you can hear when music is played too loud. In my case the volume doesn’t matter. Even on low volume I can hear the distortion. I have tried to disable all the plugin effects, but I still get the noise, but not as loud as with the plugins activated. Again, when listening through my speakers, the music sounds perfect.
I have never experienced this before. It just started today. All my projects were just fine sounding through my headphones up until today. I haven’t made changes or updates whatsoever.
make sure your sample rates are correct / consistent.
You might be sending your headphones out via two different but parallel outs?
Samples rates correct.
I found out that there must be something wrong with the input jack on my Focusrite. I get different quality in sound by moving the adapter to different positions. The funny thing, though, is that when listening to another source (Spotify for example) than Cubase, this is not a problem.
Seems like I have found at least part of the problem. Thank you for your effort in trying to help! 
If you have any more suggestions, I would appreciate your help.
Well, your in/outs look typical on this page. But do you have your Audio Connections connected correctly? Are you using the Control Room as your main out? You should. If you are NOT, and instead using the ‘Outputs’ tab connection (not the CR out), then this can create a problem (as I recall). In the way-past, I used to avoid the CR (newbee attitude) and I experienced some distortion that reminds me of what you are talking about. What I finally realized was that the Output connection feeds into the CR and this created the distortion. This - at least in my old system - created extra gain in my headphones that could only be solved by reducing the CR volume. Which was not the way CB was intended to operate in most situations. So, check that you are using the CR outs.
Lastly, if it’s not a connection issue, then maybe your interface headphone out has a problem? Good luck.