Cubase Pro 8 Audio Playback Failure

I’ve used Cubase Pro 8.0.35 for quite a while with no problems. Yesterday the audio playback stopped and I can’t get it to work again.

The playback stopped working and there is no meter activity on any track. I’m running Win 10 on a PC and I rebooted it several times but the problem wasn’t fixed. The I also tried the VST connections and ASIO driver settings just to see if reloading them would fix it but that also didn’t work.

I upgraded Cubase to 8.0.40 and the playback worked for about a minute. I was even able to start recording a track. After stopping and then restarting the track, playback failed again with the same symptoms.

By the way I read that there were problems with automation but these are simple projects that include no automation. I’m using the Focusrite 18i8.

I can’t seem to solve this and would appreciate any help.