intermittently

/ˌɪntərˈmɪtəntli/
adverb
  1. In a way that stops and starts at irregular intervals; not continuously.
    • She worked intermittently on her novel, writing a few pages one week and nothing the next.
    • The rain fell intermittently throughout the afternoon, sometimes heavy and sometimes just a drizzle.
    • The old radio signal came through intermittently, cutting in and out as the car drove through the mountains.