If a hearing aid has an "intermittent sound", which issue could be causing this?

An intermittent sound in a hearing aid often indicates a connection problem, and dirty battery contacts are a common and likely cause of this issue. If the contacts between the battery and the hearing aid are dirty or corroded, they may not make a consistent connection, leading to fluctuations in sound. This can manifest as sounds that come and go unexpectedly, as the power supply to the hearing aid is interrupted.

In contrast, a strong battery would typically result in smooth operation of the hearing aid, as it would provide sufficient power for consistent performance. New settings on the device could potentially affect the sound, but they would not typically cause an intermittent sound; instead, they might influence the volume or sound quality without interruptions. A comfortable earmold fit is largely related to physical comfort and proper sound delivery but does not directly cause intermittent sounds.