Device 7 is the wrong device, due to the fact that Device 7 refers to DEV=0. I need DEV=1 (hw:1,1).
That's my aplay -l (the device I need is in bold letters):
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC898 Analog [ALC898 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: ALC898 Digital [ALC898 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: Device [T+A USB Audio Device], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: Device [T+A USB Audio Device], device 1: USB Audio [USB Audio #1]
Subdevices: 1/1
Subdevice #0: subdevice #0
**********************************************************************************************
aplay -L (the device I need is in bold letters):
null
Discard all samples (playback) or generate zero samples (capture)
sysdefault:CARD=PCH
HDA Intel PCH, ALC898 Analog
Default Audio Device
front:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
Front speakers
surround40:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
4.0 Surround output to Front and Rear speakers
surround41:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Digital
IEC958 (S/PDIF) Digital Audio Output
hdmi:CARD=PCH,DEV=0
HDA Intel PCH, HDMI 0
HDMI Audio Output
hdmi:CARD=PCH,DEV=1
HDA Intel PCH, HDMI 1
HDMI Audio Output
dmix:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
Direct sample mixing device
dmix:CARD=PCH,DEV=1
HDA Intel PCH, ALC898 Digital
Direct sample mixing device
dmix:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct sample mixing device
dmix:CARD=PCH,DEV=7
HDA Intel PCH, HDMI 1
Direct sample mixing device
dsnoop:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
Direct sample snooping device
dsnoop:CARD=PCH,DEV=1
HDA Intel PCH, ALC898 Digital
Direct sample snooping device
dsnoop:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct sample snooping device
dsnoop:CARD=PCH,DEV=7
HDA Intel PCH, HDMI 1
Direct sample snooping device
hw:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
Direct hardware device without any conversions
hw:CARD=PCH,DEV=1
HDA Intel PCH, ALC898 Digital
Direct hardware device without any conversions
hw:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct hardware device without any conversions
hw:CARD=PCH,DEV=7
HDA Intel PCH, HDMI 1
Direct hardware device without any conversions
plughw:CARD=PCH,DEV=0
HDA Intel PCH, ALC898 Analog
Hardware device with all software conversions
plughw:CARD=PCH,DEV=1
HDA Intel PCH, ALC898 Digital
Hardware device with all software conversions
plughw:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Hardware device with all software conversions
plughw:CARD=PCH,DEV=7
HDA Intel PCH, HDMI 1
Hardware device with all software conversions
sysdefault:CARD=Device
T+A USB Audio Device, USB Audio
Default Audio Device
front:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
Front speakers
surround40:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
4.0 Surround output to Front and Rear speakers
surround41:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
IEC958 (S/PDIF) Digital Audio Output
dmix:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
Direct sample mixing device
dmix:CARD=Device,DEV=1
T+A USB Audio Device, USB Audio #1
Direct sample mixing device
dsnoop:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
Direct sample snooping device
dsnoop:CARD=Device,DEV=1
T+A USB Audio Device, USB Audio #1
Direct sample snooping device
hw:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
Direct hardware device without any conversions
hw:CARD=Device,DEV=1
T+A USB Audio Device, USB Audio #1
Direct hardware device without any conversions
plughw:CARD=Device,DEV=0
T+A USB Audio Device, USB Audio
Hardware device with all software conversions
plughw:CARD=Device,DEV=1
T+A USB Audio Device, USB Audio #1
Hardware device with all software conversions