Can't hear the ringer

Hello.

My co-worker have a Nokia 5165.
He said he used to be able to hear the ringer, but now cannot.

I tried calling him from our landlin phone and sure enough his phone
does not ring.
When we press the keys on the keypad we hear the beeps fine.

Tried four different things as described below:

1) I went online and found the user's guide:
http://nds2.nokia.com/files/support/...5165_US_en.PDF

We set the phone to this:

My Tones:
81 Ringing Options
811 Ring

83 Ringing Volume
835 Level 5

Called again from the landline, the phone indicated visually that it
was receiving a call but no ring.

2) I went to Nokia.com's FAQ search and typed in my model number and my
text
tried to search under: "can't hear the ringer" no files
then "ringer", no files
Then I searched under the string: "loud" and got some results

Chose this link and was brought to this information:

-----> Q: How can I quickly adjust my Nokia phone's sound settings?

-----> A: To choose a Quick alert setting, briefly press the Power key,
scroll to the setting
-----> you want, then press OK.
----->
-----> My tones is a setting that uses the current settings in Menu 9
(Tones).
-----> * Silent means all sound is turned off. The Silent icon appears
on the display.
-----> * Quiet means your phone beeps once when you receive a call or
text message.
-----> Other tones are turned off.
-----> * Loud means your phone rings loudly. Other tones are loud as
well.

Well, I searched for "Menu 9" in the User's Guide and it sent me to the
"Keypad locking options."
Not what the FAQ prepared me for.

3) So I went back to the .PDF user's guide and searched under "quiet"

Then I found something similar to what the FAQ told me:
But this time it directed me to "Menu 8"

I scrolled through Menu 8 and didn't see anything like Silent, Quiet or
Loud.

4) Then I decided to search the PDF user's guide for "Quick Alert"
Finally found the Quick Alert Settings and set it to "Loud"

And we still can't hear the phone.

What did we miss?

Thank you,
New