Phones have particular characteristics that affect how this works: small drivers, aggressive audio processing, and operating system behaviours that can quietly undermine the whole exercise.
For a complete overview, see our full guide: Clean dust and lint from a speaker.
The routing problem, first
Before anything else: turn Bluetooth off completely. Not disconnect — off. Phones
re-route audio to paired devices automatically and silently, and earbuds in a bag, a car
system in the driveway or a smartwatch on your wrist will all take the output. This is the
single most common reason people report the tool doing nothing.
Media volume is a separate control
Phones maintain independent volume levels for media, calls, alarms and notifications.
Pressing volume up outside an app often adjusts ringer volume rather than media volume. Start
the tone first, then adjust while it is playing — that guarantees you are moving the right
slider.
Audio processing can work against you
Many phones apply dynamic range compression, bass enhancement or loudness normalisation to
media output. These can reduce the clean sine wave the cycle depends on. If your device has
an equaliser or a sound-enhancement mode, switch it to flat or off before running cycles.
Small drivers, real limits
A phone speaker is a few millimetres across. It cannot produce useful output much below
100 Hz regardless of what you play through it, which is why the working band sits
between roughly 120 and 400 Hz. Files advertised at very low frequencies are often
inaudible on a phone not because the file is wrong but because the driver cannot reproduce
it.
Practical setup
- Case off — it overlaps the grille and traps expelled debris.
- Brush the grille first.
- 70–80 percent media volume.
- Grille down, phone angled about 45 degrees.
- Four or five sweep cycles of 30–45 seconds, brushing between them.
Which grille you are working on
Most phones have two outputs. Media plays through the bottom loudspeaker; calls play
through the earpiece. Running media cycles does nothing for a blocked earpiece — if your
problem is quiet calls rather than quiet music, the earpiece is the target and it needs
physical cleaning more than acoustic.