If your follow-up email is just "hey, just checking in," you're not actually adding anything of value to the conversation. The person on the other end needs a reason to open your next email! Not just a reminder that you exist.
New tracks. A new playlist. A new reason for them to care about what you can provide for them.
In other words, pile on the value. Earn the response from them by adding VALUE.
Next time you're about to hit send on a value-less "Follow Up," stop and ask: what am I actually giving them this time that I didn't give them last time?
Reply below with what your next "value add" is going to be, even if it's still a few weeks out.