If you are using a operating system with a language that uses a comma “,” as a decimal point “.” (French, German, Swedish, Italian, etc.),
then you will find that then using maths channels with decimal points you will have some issues.
This is because the software uses the operating system to break the numbers but it also use comma to separate variables when using function such as the high pass filter.
Unfortunately as this requires a major rewrite for the maths channel it may take a while before we are able to fix this issue.
While we are currently looking at this issue you can work around it by changing the decimal symbol of your language settings
Please go to Start > Control Panel > ...
Windows XP : Regional and Language Options>Customise
Windows Vista : Languages and Region > Customise this format.
Windows 7 : Region and Language > Additional settings
Windows 8 : Language> Change date, time or number formats > Additional Settings
And changing the Decimal symbol from a comma to a full stop.
Please accept my apologises for any inconvenience this may cause.