No connection of Audio cable

Hi,

I have a problem with my desktop.

There are built-in speakers in my pc monitor, (led monitor with speakers)

Since one week, There is no sound from the speakers.

We cannot hear windows startup sound also.

Randomly, it is connected to pc.

it is saying please connect the cable or check the cable.

But every thing is ok.

After sometime it is connecting to the pc.

I have also run the antivirus check for any virus, as I was think of it6

Please help me.