That might be caused by bad/weak micro HDMI adapter connection or the HDMI cable connection on either end.
You could try to find out by gently (really gently!) wiggling adapter and cable, one connection at time.
If it gets better (or worse) You probably found out where the issue is...
I already tried that. I still have a black screen and it kept saying "no Signal".
What are you using as the power supply and USB cable? Just another possibility...
I am using the official Pi power supply. It has a cable attached.
I inspected the Micro-HDMI-Adapter and it appeared to have a broken Contact. That would explain why it worked at first and then started freaking out before leaving the screen black. I'll go and buy a new adapter and let you know if it worked.