You navigate your iPod’s music content using either the controls on the head unit or an included wireless remote control. I have a 160GB iPod classic that hosts over 12,000 songs at last check, so navigating using the head unit was clumsy at best. You can use a “Jump” feature to automatically skip forward a specific number of songs on a playlist, but this doesn’t make the navigation of large lists any easier. This unit needs some sort of fast scrolling feature, similar to the way that the iPod will let you scan alphabetically through artist and album lists when you spin the Click Wheel rapidly.
Thankfully, the MEX-BT5700U offers a “Passenger control” setting, which lets you use the iPod’s own controls and screen. This Passenger mode is supported by most iPods except the original iPod (with video) and the first-generation iPod nano.
If you have a second-generation iPod touch or an iPhone running iPhone OS 3, you also have the option of streaming audio wirelessly over Bluetooth. That’s right—you can have a completely wireless sound system in your car. This is incredibly convenient and worked quite reliably for me once I worked out some kinks on my own iPhone 3G. Using a Bluetooth connection does run down the iPhone’s battery much faster than normal, though.
Pairing your device with the head unit is similar to pairing with a set of Bluetooth headphones or a Bluetooth headset. You enter a code on the source device, enter the code again on the head unit (using the remote control is the easiest way to do so), and the two devices connect. Any time the head unit is powered (in other words, whenthe car is running or in accessory-power mode) and the iPhone or iPod touch is on, they’ll automatically reconnect. You can even link the head unit to more than one device: my iPhone, my wife’s iPhone, and my latest-generation iPod touch were all connected at one point. However, the system will recognize only one source at a time—you change which device the Xplod recognizes as the audio source using the head unit’s Bluetooth menu.
Once paired, you can also use the MEX-BT5700U as a Bluetooth speakerphone for your iPhone. The head unit includes its own wired microphone, which can clip to your dashboard or visor. This allows for totally hands-free calling from your car, and it works pretty well, though the initial installation may involve some trial and error as you and your installer find just the right location for the mic to live. You can adjust the mic gain and the amount of ambient noise cancellation using controls built into the head unit.