Although I cannot diagnose this issue from here, I highly recommend that you contact the Samsung service center in your region for further assistance. They should be able to put you in contact with a tech that will be able to diagnose the issue.
The speakers of my monitor are making a continuous whistling noise whenever i connect my laptop to it (vga/hdmi) or the tv cable. The only way i have found to make it stop is to go and change it to use external speakers. Then when the built-in speakers are disabled the noise stops. However every time i restart the monitor the noise comes back even though the settings are still set to External speaker and i have to redo it going external-> tv-> external in the menu again to make it stop. Also ive noticed when I'm watching tv using the inbuilt speakers if i turn down the volume to 0 i can still hear the noise but if i mute it with the mute button it goes away. If there isn't anything connected to the monitor the speakers are quiet, but the moment i connect anything to it they start making this annoying sound. What could be the cause of this?