SCORM cmi.core.total_time often inconsistent

Hello,
We experience inconsistent SCORM cmi.core.total_time, meaning that the same SCORM registers normal time values but also near-zero values in a pool of hundreds of users with different browsers and devices..
These are the settings of the modules which might not be right now that I look better at it but that's how they were. 
Force completed                      No                   
Auto-continue                          Yes         
Auto-commit                            No      
Mastery score overrides status Yes
 
We are running Moodle 3.9+ and getting ready to upgrade.
The courses should take hours also because they are locked in with forced navigation.
The low values are like 

There are also too large values:

Regards,

Aida