C'était également le hw 0,7 pour mon T460 :

aplay -D plughw:0,7 /usr/share/sounds/alsa/Front_Center.wav

load-module module-alsa-sink device=hw:0,7 channels=2 rate=48000 sink_properties=device.description=HDMI

"""
Please keep in mind that most PC video card (Nvidia, AMD) do not support CEC(see PS2,PS3). The one known(have clear documentation/specification) GPU that support CEC is VideoCore, found in Raspberry Pi.
Base on online forum post, Nvidia (GF, GT(ION), GTX) never claim to support CEC, nor deny. Nvidia website has no info about CEC. It basically don't say anything regarding this. I just take that as a "NO".
"""

il y a aussi les cubox-i et les cubieboard3 qui gèrent le CEC.