Hi Takashi,

I enumerated all the DELL DisplayPort monitors in our lab and find only two of them being able to produce audible DisplayPort audio...

- DELL 2408WFP - DELL 2709W - DELL 3008WFP no CEA extension found

- DELL U2410 ELD reports OK but cannot hear DP sound

monitor_present 1 eld_valid 1 monitor_name DELL U2410 connection_type DisplayPort eld_version [0x2] CEA-861D or below edid_version [0x3] CEA-861-B, C or D manufacture_id 0xac10 product_id 0xf017 port_id 0x0 support_hdcp 0 support_ai 0 audio_sync_delay 0 speakers [0x1] FL/FR sad_count 1 sad0_coding_type [0x1] LPCM sad0_channels 2 sad0_rates [0xe0] 32000 44100 48000 sad0_bits [0xe0000] 16 20 24

- DELL U3011 ELD and DP sound both OK

monitor_present 1 eld_valid 1 monitor_name DELL U3011 connection_type DisplayPort eld_version [0x2] CEA-861D or below edid_version [0x3] CEA-861-B, C or D manufacture_id 0xac10 product_id 0x4065 port_id 0x0 support_hdcp 0 support_ai 0 audio_sync_delay 0 speakers [0xf] FL/FR LFE FC RL/RR sad_count 1 sad0_coding_type [0x1] LPCM sad0_channels 6 sad0_rates [0x1ee0] 32000 44100 48000 96000 176400 192000 384000 sad0_bits [0xe0000] 16 20 24

- Eizo FlexScan EV2333W ELD and DP sound both OK

monitor_present 1 eld_valid 1 monitor_name EV2333W connection_type DisplayPort eld_version [0x2] CEA-861D or below edid_version [0x3] CEA-861-B, C or D manufacture_id 0xc315 product_id 0x2068 port_id 0x0 support_hdcp 0 support_ai 1 audio_sync_delay 0 speakers [0x1] FL/FR sad_count 1 sad0_coding_type [0x1] LPCM sad0_channels 2 sad0_rates [0x1ee0] 32000 44100 48000 96000 176400 192000 384000 sad0_bits [0xe0000] 16 20 24

Thanks, Fengguang