There is only one file type that uses the .WFP extension:
WaveFront Program File
A WFP file contains a single program, or patch, used by Turtle Beach WaveFront synthesizer cards. It represents an instrument that can be added to a WaveFront synthesizer. WaveFront-based synthesizers include the Maui, Tropez, Rio, and Monterey.
Since the mid-2000s, Turtle Beach has primarily produced gaming headsets and other gaming accessories, abandoning the sound card and synthesizer market. As such, you're unlikely to encounter a WaveFront Program File.
You can open WFP files using FMJ-Software Awave Studio.
Updated: September 22, 2020