A wolf tone is a sustaining sympathetic artificial overtone that amplifies and expands the frequencies of a played musical note, and is produced when the original note matches the natural resonant frequency of the body of the musical instrument.
In general, this can be solved easily by putting a wolf tone eliminator on your instrument. This will augment the mass of the instrument and alter the natural frequency of the instrument.
This chromed wolf eliminator is easy to install.
For violin and viola.