Early indications here are that updating the ALSA drivers fixes the
problem. I've usually noticed the problem when coming in to work and the
machine has been suspended, I did that whole thing now and reconnected
external display + headphones and I got proper sound. Seems promising.
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You receive
Actually, I can add that it isn't only when connected via headphones. If
I connect to my TV at home and play a movie for example, the same thing
happens - sound is seemingly half speed. Just mentioning this since it
indicates it is entirely a problem with HDMI rather than headphones +
hdmi combo. A
Same problem here. Asus Laptop UX305fa. Half-speed sound when connected via 3.5
mm to external monitor conntected via HDMI.
For me this started happening after upgrading from 15.10 to 16.04. I can get
around the issue by rebooting my machine after connecting the external
monitor... which ofc isn