Constant LESS CSS Compiler Error

[jamiebeech]

I'm started working on an existing project with several developers and they are having no issues compiling the LESS or seeing any errors, yet everytime I seem to make an amendment to a file it throws a different LESS CSS Compiler Error usually saying something is undefined when it is not.
For example:

LESS CSS Compiler Error
app.nav.less: Name Error: variable @brand-light is undefined (line 39, column 34) near .bg-light & { border-bottom: 1px solid darken(@brand-light, 3%); }

[jamiebeech]

I'm running PHPStorm 8.0.3, using version 2.6.9 of the LESS CSS Compiler on OSX if that is any help.