iPhone not ringing on new text/mail.

[Katanae]

So does anyone have this problem?
My Phone is not in silent mode but it appears that it randomly only vibrates on new texts and mails.
Is this a known bug?

 

[Katanae]

Forgot to mention it is a jb. iPhone 4.

Any help would be appreciated.

 

[acfusion29]

Forgot to mention it is a jb. iPhone 4.

Any help would be appreciated.

i have this problem on my non-jailbroken iPhone 4. running 4.1

except, i've only noticed it when the vibrate is on (since it's on most of the time). i'll get a message and it won't even vibrate.