9.5.50 audio issue

Hi all.
I updated to 9.5.5 on Monday and now none of my audio tracks can be heard in or out. VST instruments are fine.

I can play the exact same projects in 9 and 10 - trial version no problem - audio in audible and audio out audible.

How can this be possible??

Does anyone know what has gone wrong?

Thanks in advance :smiley:

Update - removed 9.5.5 - reinstalled 9.5.3 (havenโ€™t got 9.5.41 on my disc) all works as normal.

This issue is definitely a 9.5.5 problem.

Can you help me Steinberg?