Not regularly
Synonyms:
  1. off-and-on
  2. alternately
  3. at irregular intervals
  4. fluctuating
  5. inconstantly
  6. infrequently
  7. intermittently
  8. irregularly
  9. not often
  10. now-and-then
  11. sometimes
  12. sporadically
  13. uncertainly
  14. variable
  15. very seldom
  16. when the mood strikes