What is the input voltage of the charging case? December 06, 2023 16:37 Updated MDHearing's charging cases for our rechargeable hearing aids have an input voltage of 5VDC via the USB-C cable. Related articles What is the charging voltage of the hearing aids? Which program should I use with my VOLT MAX? Is the MDHearing app able to stream music/TV to the hearing aid? How do I charge the VOLT and VOLT+? Why isn't the MDHearing app connecting to my hearing aid?