Sound not working when headphones unplugged

[Vit72]

.After the certain moment, my speakers don't work, when the headphones get unplugged (3.5 mm jack). There is only speakers icon in playback tab, no matter, whether headphones are plugged in or not.
Is there a way to determine, whether windows7 detects the headphone jack as plugged in, even if it's not? (that would be hardware problem then, I guess). If so, how to disable jack detection, so that the speakers can get unblocked? Or suggest any other solution. Thanks for replies.

 

[DelJo63]

It's not a software problem.

The phone jack on the PC has a switch which is likely to be failing, especially if the machine has a few years on it and you've over time switch between the headphones and the speakers frequently.

The switch allows speaker output when the phones are disconnected and disallow when connected. So even though you have physically disconnected the headset, the switch is not reconnecting to the speakers.