I connect my Win 7 computer to set top box via HDMI to display TV. The problem is I must turn the volume way up to hear TV. But when going back to regular computer use the volume is way too loud and must turn it down. And if an audio email (MS Office Outlook) notification happens while on HDMI TV the whole neighborhood can hear it because it is so loud.
You could try to adjust (increase) the volume from your set-box .
The TV audio volume is controlled by the computer. the set top box has no volume control.
click on the speaker icon in the system tray of the PC, select "mixer", then you can adjust volumes for various different things. Like keeping system sounds down while speaker general volume up.
HDMI though any device requires the other main device to be disabled as in if you are using onboard sound Disable it
Then let your TV be the default sound it would show up in audio as default device or even the dropbox select that as main audio and it should override the onboard thus bringing the true volume
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