Toyota TUNDRA 2009 Manual page 367

n Automatic adjustment of volume
When vehicle speed is 50 mph (80 km/h) or more, the volume automatically
increases. The volume returns to the previous volume setting when vehicle
speed drops to 43 mph (70 km/h) or less.
When using a voice command
n
l For numbers, speak a combination of single digits from zero to nine, #
(pound), ∗ (star), and + (plus).
l Speak the command correctly and clearly.
The system may not recognize your voice in the following situations:
n
l When driving on a rough road
l When driving at high speeds
When air is blowing out of the vents onto the microphone
l
l When the air conditioning fan emits a loud noise
The following cannot be performed while driving:
n
Operating the system with
l
l Registering a cellular phone to the system
n Changing the passkey
→P. 380
3-4. Using the hands-free phone system (for cellular phone)
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