When you turn ON Auto-Refill, we will automatically charge your credit card or PayPal account when your Stream balance is “too low”. Your Stream balance is deemed to be “too low” when your usage pattern indicates that you have less than a week’s worth of Audio Streams remaining. So the “low balance” threshold is not an absolute number, but computed according to your usage. This allows the account to be automatically replenished and avoid possible interruptions in service.
Customer support service by UserEcho