I am having a similar issue after updating to latest today. I use the virtual software sensor to get an output delta between liquid and ambient temperature. Now all sensors output 100 into the virtual sensor even though the data source shows the correct temp. now all my fan curves are trashed.
I've restarted the system multiple times and no luck.
It looks like it is pulling from the fallback value even though the data source does have the correct value.
Update: Virtual software sensor will not pull from quatro sensors. It will pull from vision sensors though.