Minimizing or Eliminating Noise
Make sure to turn the volume all the way up on your iPhone first, then adjust the volume on your speaker system for the cleanest sound.
Noise (static/clicking/popping - click to listen) is the most common complaint I receive from customers when installing the AirEnabler in the car. The noise is typically caused by a ground loop and is dependent on your car. For instance, in my 2009 Honda CRV, my stereo and cigarette lighter port are grounded to the same location (see picture below) and I have zero noise. If you suspect that you're experiencing a ground loop issue, you can verify by testing the AirEnabler in your house using the included AC USB Charger. If the AirEnabler sounds clean in your house but not in your car, chances are you have a ground loop issue.
Here are some ways to resolve ground loop noise:
Options to Eliminate Boot Up Time
This section is for the people who can not wait the 40 seconds for the AirEnabler to power on. Basically the solution is to keep the AirEnabler powered on all the time. Note that, the AirEnabler is very energy efficient; using only 100ma on idle.
1) Hardwire a Micro USB 12V to 5V Converter Cable to your vehicle's fuse box using a Fuse Tap (Add-A-Circuit Kit) and pick a fuse slot that provides a constant 12V current even when the car is off, such as for your brake lights. If your battery is in good condition and you drive daily, you should not run into any issue considering the low 100ma power draw of the AirEnabler. If you plan to park your car for extended period of time, you'll have to remember to unplug the AirEnabler.
2) Power AirEnabler by a large External USB Battery Pack. This is a super simple solution. The External USB Battery Pack is charged while the car is running. When the car is off, the AirEnabler is powered from External USB Battery Pack. Note that your External USB Battery will wear from constant use and may require replacing. Also, your driving time may not be sufficient to keep the USB Battery Pack charged. Greater than 7000mAh capacity battery recommended as most external USB Battery Pack manufacturers overstate actual capacity. Note that some USB External Battery Pack will power cycle the USB port (AirEnabler) when a charge is applied (when the car turns on) or will not charge while being charged. This is dependent of the External USB Battery Pack. Look for a USB Battery pack that supports "pass through charging" which supports charging while being charged. Please drop me an email - firstname.lastname@example.org - if you have a recommendation on a External USB Battery pack that is working well for you so I can share it with others. Thank you.
Reported as Working:
3) Keep AirEnabler powered on constantly like option 1 with the addition of a Battery Discharge Prevention Device (aka Low Battery Cutoff) eliminating the risk of a drained battery. This is the Ideal and recommended solution if you want to keep the AirEnabler powered on all the time and don't want to take any risk.
4) Another creative solution some customers have pointed out is to tap into your car's overhead dome light fuse (or the glovebox flashlight port in BMWs) which is activated when the car doors are unlocked. This would allow the AirEnabler's boot up process to get a head start, saving you 10-20 seconds.
Minimizing Cables / Eliminating the need for the USB Car Charger
Pictures (because pictures are always nice)
Kensington and PAC Ground Loop Isolators - Both work equally well. The biggest difference would be that the Kensington has two 3.5mm male connectors and the PAC has a male and female.
USB Isolator - plugged in between the AirEnabler DAC to provide a nice noise free connection. Note that if you get the BBTech or Generic USB Isolator, you can plug it inbetween the AirEnabler and USB power source.
The major difference between the three is the form factor and maximum mA output current. I like the BBTech USB Isolator for its compact size and high output current. However it only ships from Taiwan, so be prepared to wait at least two weeks for it. The Generic Ebay USB Isolator is a great alternative and ships from the U.S.
BBTech USB Isolator with Turtle Beach Audio Advantage Micro II USB Analog & Digital Audio Adapter (Note that the Micro II is a USB 1.1 device which typically requires a USB hub to work with the AirEnabler. However, using the USB Isolator eliminates the need for the USB hub)
Generic Ebay USB Isolator with Creative Sound Blaster X-Fi HD USB Audio System with SBX SB1240 (Note that the HifimeDIY USB Isolator was not able to provide enough power for the SB1240)
Stereo and Cigarette Lighter Port Properly Grounded in Central Location