I have an HDTV Monitor connected via HDMI with the audio, and i have an external speaker connected to line out. Is there a way to get both of the devices to play the same audio source at the same time without switching?
Short answer is NO.
You can only have one default audio playback device, either the HDMI or "speakers" (Your PC sound card).
There isn't a "long answer". That is the way Windows works and from other identical questions on here and on the Dell forum there does not appear to be a way around this, that I've seen.
The only possible way would be to use a stereo "Y" cable from the PC"s speaker output (e.g. Green speaker jack) and connect one side of the Y cable to your speakers and run a cable from the other side of the Y cable to an analog audio input on the HDTV (if the HDTV is capable of using HDMI for video and a separate analog audio input for sound).
I might consider getting DVI (Taking a step up from VGA) then since it does not carry sound, I could just connect that to audio input on the HDTV.
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