Audio Fix / setup help
S.M.S.L SU-9 Pro: compare one higher documented DPLL setting
S.M.S.L SU-9 Pro — compare one higher documented DPLL setting. Use the stated exact hardware and connection scope.
Manufacturer-documented Reviewed 2026-11-09 · Revision 1
Follow these checks in Audio Fix →When this guide applies
Exact S.M.S.L SU-9 Pro. A correctly connected supported optical source intermittently loses playback, and the exact DAC DPLL is below its available maximum. This is an input-tolerance comparison, not a guaranteed hardware repair.
Connection scope: Optical digital audio. Symptom: Audio keeps cutting out.
This is a documented check, not a diagnosis of your equipment. The model name does not confirm the selected input, mode, software or connected partner.
If your exact model or a required setting is unknown, use the “I don’t know” branch below. Do not apply a similarly named model’s instructions.
Checks and possible outcomes
Start at scope. Follow the link that matches what you actually observe. Alternative branches are not a single sequence of actions.
scope
Confirm the model and connection
A correctly connected supported optical source intermittently loses playback, and the exact DAC DPLL is below its available maximum. This is an input-tolerance comparison, not a guaranteed hardware repair.
Look for: Confirm this exact setup and observation before continuing.
- If Yes, I confirm → Accept temporary optical unlock/interruption?
- If No / my setup differs → Continue with source and model support
- If I cannot confirm → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
dpll-consent
Accept temporary optical unlock/interruption?
A DPLL change can interrupt lock/audio. Continue only outside calls/recordings, with agreement to pause and reduce listening level before the reversible comparison.
Look for: Explicit informed acceptance is required before the next action.
- If I accept these effects → Pause optical media
- If No / leave this unchanged → Continue with source and model support
- If I cannot confirm → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
a1
Pause optical media
Pause the already-connected supported optical source.
Look for: Observe the named indication or available control; stop if absent.
- If I completed this check → Reduce the listening level
- If I cannot complete this → Continue with source and model support
- If I cannot determine this → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
a2
Reduce the listening level
Mute downstream amplification at its own minimum level control.
Look for: Observe the named indication or available control; stop if absent.
- If I completed this check → Record DPLL
- If I cannot complete this → Continue with source and model support
- If I cannot determine this → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
a3
Record DPLL
Open DPLL using the remote menu and record its actual current value. Continue only if a higher valid setting remains available; do not assume a default.
Look for: Observe the named indication or available control; stop if absent.
- If I completed this check → Increase DPLL by one step
- If I cannot complete this → Continue with source and model support
- If I cannot determine this → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
a4
Increase DPLL by one step
Choose one higher available DPLL value without altering source format, output or PRE mode.
Look for: Observe the named indication or available control; stop if absent.
- If I completed this check → Compare the same material
- If I cannot complete this → Continue with source and model support
- If I cannot determine this → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
a5
Compare the same material
Resume the same optical media at low level and compare interruption frequency. If worse, pause before restoring the recorded setting; never increase volume to compensate.
Look for: Observe the named indication or available control; stop if absent.
- If I completed this check → Check the result
- If I cannot complete this → Continue with source and model support
- If I cannot determine this → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
observe
Check the result
Is the same optical media stable at the one-step-higher DPLL setting?
Look for: Confirm this exact setup and observation before continuing.
- If Yes, I confirm → Checks completed
- If No / my setup differs → Continue with source and model support
- If I cannot confirm → More information is required
- Manufacturer-documented S.M.S.L SU-9 Pro — official manual ↗English pages 14–19: remote, Bluetooth, outputs, PRE, SOUND COLOR, DPLL and brightness — SU-9 Pro is a line DAC, not headphone amp. INPUTS selects USB/BT/optical, OUTPUT selectsAll/Balanced/Unbalanced. PRE VARIABLE controls volume, FIXED ignores it. SOUND COLOR Standard bypasses effects; DPL Llarger improves input tolerance. Bluetooth long press clears pairing, excluded; menu INPUTS permits ordinary BT selection.Exact S.M.S.L SU-9 Pro. · Source checked 2026-11-09
Possible result
More information is required
An unknown state is not a diagnosis. Record the last visible indication and consult the exact model instructions.
insufficient data
Reaching this result does not mean the issue is solved. Only your own feedback can report improvement.
Possible result
Continue with source and model support
Keep the source, connection and last observation. Do not reset, open equipment or change full-scale output to compensate for an unconfirmed result.
next support
Reaching this result does not mean the issue is solved. Only your own feedback can report improvement.
Possible result
Checks completed
The requested observation was confirmed in this setup. It does not establish a hardware repair or guarantee another source behaves the same.
steps completed
Reaching this result does not mean the issue is solved. Only your own feedback can report improvement.