Simply want to turn ringer off at my phone for external incoming calls

Go into the extension programming and change the line settings to no ring. It is best done if you have a display phone so you can see the changes. If not, then you will need to look at the flashing line lights when you enter the programming mode.

Press Feature 00. This will take you into the programming mode. You should see the line buttons lit up green. They will be Solid (Immediate Ring) or Slow Flash (Delayed Ring) or Fast Flash (No Ring). I assume yours is solid so push each line button until it changes to a fast flash. Once done press Feature 00 to exit the system and save the settings.

Here some solutions for your problem + a link to the user manual.

**Selecting the Ring Tone and Volume
Your phone has five different ringer tone/volume combinations you can choose from.
To select the ringer:
1) With the phone in standby, press [vol/ / ] or [vol/ / ].
2) The phone will sound the different ring tones at different volumes. To turn the ringer
off, select RINGER OFF.
3) When the phone sounds the ring tone and volume you wish to use, press [end].


**Temporarily Mute Ringer
If the handset is off the base while an incoming call is ringing, simply press [end] to mute
the incoming ring. The ringer will sound with the next incoming call.
Note: You can only mute the handset ringer if the handset is off the base when the phone starts
ringing.
Adjusting the Earpiece.

**Here is also a link to the phone manual http://www.uniden.com/pdf/EXI4561om.pdf

Follow the below instructions and you can remove the vibrate state. I have included a link to download the phone's manual as a PDF file.

Sound Settings
Ringer Types
Ringer types help you identify incoming calls and messages.
You can assign ringer types to individual Contacts entries,
types of calls, and types of messages.
Downloaded Ringers can be downloaded right to your
phone.
Preprogrammed Ringers include a variety of standard
ringer types and familiar music.
Vibrating Ringer alerts you to calls or messages without
disturbing others.
Selecting Ringer Types for Voice Calls
Your phone provides a variety of ringer options that allow you
to customize your ring and volume settings. These options
allow you to identify incoming calls by the ring.
To select a ringer type for voice calls:
1. Select Menu > Settings > Sounds > Ringer Type >
Voice Calls.
2. Select With Caller ID or No Caller ID.


http://downloadcenter.samsung.com/content/UM/200708/20070824101259031_sprint_m300_ug.pdf

Incoming line ring settings are in the config menu under:
2nd option - Line access
enter extension number
2nd option - Ringing
Ringing then can be toggled on or off for each line assigned to that extension.
Mark

If you use strata emanager it would depend on how your system was set up. One way is to go to Advanced configuration tab Station tab, multiple call group tab, click on the group number (far right), then member tab and select extention and ringing option. Another way is to go again from the advance configuration tab, then assignment tab select the extention number on the right select key assignment tab, and on the incoming extention line double click it nd select no ring.

in system programming

There are two ways 1) as your looking at your phone on the top left side of the unit there is an little toggle switch to turn the ringer of or down just a bit. 2) (navagator key) in the bottom right hand corner there is a circle with four arrows on it simply press the down arrow until it says ringer off

Hi at the back of the phone you will see a selectable Hi/Lo/Off switch. Slide the (Ringer) switch to High position or Low position to turn the ringer on. Hi for high volume Lo for low volume.

To prevent hearing any ringing of incoming calls slide the (ringer) switch to the off position but when you ready to accept incoming calls again remember to slide the switch back to either Hi or Low setting. Hope this made sense and helped.

try turning ringer speaker volume down. if that does not work, then remove battery for 10-15 minutes and replace and try again.