Length sorts as Text, not Numeric

If you sort the Length column, it seems to sort as Text, not as Numeric

How is your length-column defined? (Value, Sort by ..)

%_length% represents the formatted output - which is an alphanumeric string more or less.

To get a numeric treatment set these properties in the column definition:
sort by: %_length_seconds%
numeric: ticked.

Also see this fixed bug:

Thanks to all

The 'Sort By' works great

I didn't understand that field