Ooma Forums

Just purchased an Ooma Telo and an AT&T Trimline 210M telephone for my sister. The telephone has a three position handset volume control that has been set to the lowest setting. The handset volume is still so loud that the telephone service is not useable. I called Ooma support but the technician couldn’t help. (I have a eight year old Ooma Telo with a reasonable volume level.) Any solutions? Different telephone? This is urgent. Please help.

I see this is an old post but I thought the same with all of my corded phones, some are AT&T, some are old 2564 sets (traditional phones with keys for several lines and hold). I ended up putting a 400 ohm resistor in series with both tip and ring (the 2 wires) from the Telo. On 2 AT&T electronic corded phones I use most often I even put a resistor in series with one of the receiver leads even though they're set at the lowest level. A mechanical bell and electronic ringers work fine with the 400 ohm resistors.

All the electronic AT&T corded and cordless phone are set at the lowest handset volume level. Before the modifications the receive level was significantly louder than the former telco central office line, and too loud.

If you have the AT&T Trimline phone (Model 210) you can go into the base and cut the red and green wires. Then using two 560 ohm resistors (color code Green/Blue/Brown) and some heat shrink tubing, place them in series with the jack wires in the bottom of the base as there is ample room there vs the handset. This made the time & temp phone number (614-281-8211) just the right volume and you no longer have to move the handset away from your ear. Without the resistors installed, the phone was so loud it was acting like a speaker phone. Now the Ooma is 100% useable and I don't have to send it back for a refund.