Pioneer AVIC-S2 - Manual (Page 37)

4.6 Receiving a Call
When you have a call after pairing with a mobile phone, the device rings and
displays the Incoming Call screen.
Mute Reject Accept
To accept the call, tap the Answer button.
To reject the call, tap the Ignore button.
To mute the ring tone before receiving or rejecting, tap the Mute button.
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