one more thing getting back to this https://www.kernel.org/doc/Documentation/sound/alsa/HD-Audio.txt
I cant find any Hint String with key loopback Hint Strings ~~~~~~~~~~~~ The codec parser have several switches and adjustment knobs for matching better with the actual codec or device behavior. Many of them can be adjusted dynamically via "hints" strings as mentioned in the section above. For example, by passing `jack_detect = no` string via sysfs or a patch file, you can disable the jack detection, thus the codec parser will skip the features like auto-mute or mic auto-switch. As a boolean value, either `yes`, `no`, `true`, `false`, `1` or `0` can be passed. The generic parser supports the following hints: - jack_detect (bool): specify whether the jack detection is available at all on this machine; default true - inv_jack_detect (bool): indicates that the jack detection logic is inverted - trigger_sense (bool): indicates that the jack detection needs the explicit call of AC_VERB_SET_PIN_SENSE verb - inv_eapd (bool): indicates that the EAPD is implemented in the inverted logic - pcm_format_first (bool): sets the PCM format before the stream tag and channel ID - sticky_stream (bool): keep the PCM format, stream tag and ID as long as possible; default true - spdif_status_reset (bool): reset the SPDIF status bits at each time the SPDIF stream is set up - pin_amp_workaround (bool): the output pin may have multiple amp values - single_adc_amp (bool): ADCs can have only single input amps - auto_mute (bool): enable/disable the headphone auto-mute feature; default true - auto_mic (bool): enable/disable the mic auto-switch feature; default true - line_in_auto_switch (bool): enable/disable the line-in auto-switch feature; default false - need_dac_fix (bool): limits the DACs depending on the channel count - primary_hp (bool): probe headphone jacks as the primary outputs; default true - multi_io (bool): try probing multi-I/O config (e.g. shared line-in/surround, mic/clfe jacks) - multi_cap_vol (bool): provide multiple capture volumes - inv_dmic_split (bool): provide split internal mic volume/switch for phase-inverted digital mics - indep_hp (bool): provide the independent headphone PCM stream and the corresponding mixer control, if available - add_stereo_mix_input (bool): add the stereo mix (analog-loopback mix) to the input mux if available - add_jack_modes (bool): add "xxx Jack Mode" enum controls to each I/O jack for allowing to change the headphone amp and mic bias VREF capabilities - power_save_node (bool): advanced power management for each widget, controlling the power sate (D0/D3) of each widget node depending on the actual pin and stream states - power_down_unused (bool): power down the unused widgets, a subset of power_save_node, and will be dropped in future - add_hp_mic (bool): add the headphone to capture source if possible - hp_mic_detect (bool): enable/disable the hp/mic shared input for a single built-in mic case; default true - mixer_nid (int): specifies the widget NID of the analog-loopback mixer Could you advice please -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1540372 Title: [Intel DP35DP, SigmaTel STAC9271D, Green Speaker, Rear] Underruns, dropouts or crackling sound To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1540372/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs