The origin of C Cos Ia Disc Nu is not clearly documented, and the title appears to be a shortened fragment rather than a full phrase from a known film or show. Short, context free clips like this spread on user generated soundboards because they are easy to reuse in many situations. Editors keep it for quick reaction moments, random cutaways and deliberately confusing edits, where the lack of a clear source is part of the appeal and the sound works purely on timing.