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Question: How do I get device to stop popup screen that says, "USB Source detected, do you want to connect to a mass storage?" each time I start my Truck?
Document: This dashcam works exactly as advertised. I have used several, but this is the only one with GPS. I love all it does, but, when first turning it on, it always asks if I want to connect to my big computer. I haven't figured out how to stop it, and I think I never will.Further experimenting has shown that it asks if I want to connect to the computer because it sees the USB plugged in. The cam is best used while plugged in to external power.
Once connected, the camera asks if I want to use mass storage mode.
The rearward facing view screen dims when driving so there is no distraction. The power cord from the camera to the vehicle power source is not a big deal -- It does not get in the way of my Slap Paddle (gear shift gizmo) or my MP3 Aux cord. Any minor inconvenience would certainly be nullified in the event of a crash caused by CellTele engaged idiot running his/her stop. I've had PLENTY of close calls in the traffic-volume dense W,DC Capitol area.
I own all three of them and all three of them I bought from Amazon.UPDATE 5/7/14 I took the unit on the long trip. It would freeze about 10 to 15 times a day.Will be returning it tomorrow.There is one more good thing about the garmin dash cam I forgot to mention.The start up time is MUCH better than the other dashcams.Which is super important in my opinion (the sooner you start recording in critical situation the better.)
Not a big deal but I will have to take it down all the time as it will probably melt in the AZ sun.A quick disconnect would be nice.Spec says 130 degrees F temperature max. I have measured my car interior at 140 degrees not in direct sunlight when parked.Seems to use a lot of compression on snapshot photo that creates some artifacts.
The camera works great. Video is sharp. Nothing to do,  Just start the car...and the camera comes on. Shut the car off and camera goes off. It also has lots of features . Only con. Is there is a power off button on the side off the camera,  every time  you move or turn the camera for adjustment  you make the mistake and cut it off. Due to the bad location of this power switch.
I've had this camera installed in my Jeep Grand Cherokee Summit for over one month. This Garmin Dash Cam is a GREAT product. It's worth every penny! The instructions were clear and concise. The install was as easy as a Garmin GPS. The SD Micro and Adaptor are included. The SD video playback works automatically and effortlessly in my Dell XPS12 Win8.1 computing environment. The settings are reasonably intuitive; it is a shallow learning curve and may take a couple of attempts to get where you want to be.
If an event occurs, you are there and presumably know where you are so why do you need GPS?After more consideration; having GPS capabilities provides a precise time of day and also allows the device to record your speed. This could come in handy if you are trying to prove that you were not exceeding the speed limit should an event occur.I opted for GPS capabilities.Windshield mountAccording to some reviews there is concern that the suction cup windshield mount may not be optimal.
I got used to the thought that if someone is approaching my car (not even touching it), my dash cam will record it. Garmin is not capable of doing it.- it will not be easy to connect Garmin dash cam to the 12v from the car as it requires 5v.
I really want this thing to work. It is exactly what I have been looking for.
Answer: I think the issue is that you are plugging the device into a USB power source on your truck instead of using the twelve volt Power source that used to be used for cigarette lighters. Any time you plug your device into the USB plug on new vehicles the vehicle system assumes that it is an audio source. Whereas if you plug the USB into a plug receptacle in the twelve volt source it then just powers your dash cam.