I have a Uniden set of of phones - 5.8 GHZ. Both are making a loud static sound when you turn it on. We can hardly hear. We unplugged both sets for a while, but this did not get rid of the static sound.

go to settings in the phone and turn it down there

Turn up your SQUELCH button when no one is talking until the static noise just goes away.

Now your set will remain quiet until someone talks.

If you set the squelch too high it will also cut out the people talking, so always try to have it set just slightly above the background static level.

Good luck.

press and hold CID button for 5 seconds to access the phone's menu.

Then change ringer type and volume.

For the phone breaking up, try different channels of that phone to receive better frequency. The phone with the weird battery may have faulty or bad battery or charger contacts that need to be cleaned with rubbing alcohol and need to be resoldered.

I had the same issue that started on some 3 year old 5.8 GHZ Uniden cordless phones. I moved it from room to room and same buzzing. I found a older Uniden set I had kept in a desk drawer. I swapped out the power transformer (power cord) and it is clear as a bell now.

I found my owners manual and to adjust the ringer on either the Base Station or Hand Set as follows:
with the hand set in place just use the base arrow up or down to go from 0 (off) to 2 (loud) and on the hand set just use the arrows for high low or off. Just bew sure to have the hand set on the base before adjusting the ringer

jackgee1

Reset the base by unplugging power from back of base, press and hold the delete key while reconnecting power

What model Uniden 5.8GHz phone?

I solved this exactly problem by doing this:
1) unplug base station from phone line
2) unplug base station from power cube
3) open each phone and disconnect battery (do not replace phone in charger; just let it sit)
4) wait 30 minutes (per instructions from Uniden)
5) reconnect batteries in phone sets
6) reconnect power cube to base station
7) reconnect base station to phone line
8) test: make a call. Hang up. Wait one minute. Pick up line and see if you get a dial tone.
(Basically you're "rebooting" the system. You don't know where the fault lies, so you power down every component to make sure you get it. The '30 minutes' is longer than I'm used to, but after being on hold with Uniden tech support for 20 minutes and finally getting through, the instructions from them were very clear: AT LEAST 30 minutes. OK! I did it - and it worked!)

If it's in warranty, I would send it back. It sounds like a problem with the built-in amplifier and possibly other components.
The squealing and echo is down to gain being too high, if you cannot set this on the phone, then it's a fixed value in the hardware. If you can, lower the gain. As for not being able to end the call, what about pressing the "c" button or the green button again?

FIRST YOU MUST DETERMINE IF THERE IS STATIC ON YOUR PHONE LINE. EVEN WITH DSL THERE CAN BE STATIC EVEN IF THE INTERNET IS WORKING. IF YOU HAVE A CORDED PHONE TAKE IT OUT TO THE PHONE INTERFACE BOX AND OPEN THE BOX / THERE SHOULD BE A PLACE YOU CAN UNPLUG YOUR WIRING FROM THE PHONE COMPANY. PLUG YOUR PHONE INTO WHERE YOU UNPLUGGED THE WIRING AND SEE IF YOU HAVE STATIC THERE. IF YOU STILL HEAR STATIC IT IS THE PHONE COMPANY'S PROBLEM.

SOMETIMES UNPLUGGING FROM BOTH THE PHONE LINE AND THE POWER SOURCE AND REMOVING THE BATTERIES WILL CORRECT SOME PROBLEMS. FOR SECOND PHONES ON A SYSTEM THEY MUST BE REGISTERED TO THE BASE. ONCE IT IS REGISTERED IT SHOULD SHOW A NUMBER IN CORNER OF SCREEN (2)
THE MANUAL SHOULD TELL YOU HOW TO REGISTER SETS. IF YOU HAVE LOST YOUR MANUAL SEE IF YOU CAN DOWNLOAD ONE FROM THE WEB SITE OR CALL VTECH 1-800-595-9511