Send only video out with HDMI cable
You haven't said which operating system you're using, but on Windows I believe you can just change the default playback device in via the Sound control panel applet. It will probably change to HDMI automatically when you plug the cable in, but then you should be able to just go into control panel and switch it back to your laptop.
Alternatively, your media player may have options for which device to use for sound.
Follow these steps after connecting the HDMI cable.
- go to control panel
- Hardware and Sound
- Manage Audio Devices
- if you have a branded audio set-up (eg. BEATS) make changes there.
- Select speaker/HP
- make Default and apply
This will work if you have Windows 7 and 10.
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if you have Windows 7, go to Control Panel → Sound → Manage Audio Devices. In Playback disable the device (e.g. Samsung if you have a Samsung external monitor) by selecting and right clicking the device.
You can re-enable the desired audio output source as required. Make sure you also right click and check Show Disabled Devices.