Hi,
What version of FMOD Studio and Integration are you using? What version of Ue are you using?
An option may be setting the Async instrument to infinitely loop (FMOD studio | Working with Instruments - Looping Instruments):
and adding a loop region (FMOD Studio | Glossary - Loop Region) around the programmer instrument.
The loop behavior keeps the instrument playing while the loop region keeps the event playing.
Hope this helps!