It seems there is still no such function. I'd also appreciate to have such high-performance 1-dimensional interpolation algorithms inside IPPS.
Typical usage for audio processing might be to interpolate from third-octave or other low-resolution values to full-sprectrum filters for FFT processing.
In general I think there are plenty of applications for interpolation. The beforementioned "interp1" from MATLAB is a frequently used function amongst signal processing folks.
Thanks for considering this in a future release!