[MTCB Android Head Units General] Restrected:
Well, the low pre-amp outputs are that way on purpose.

Here is how it works.

If you go to factory settings, enter the password "126", click OK, it will give you basic settings for the unit.

That is how you change the boot logo. I have mine set to VW since that is the car i have.

You can change GAIN for all audio type outputs. Say system, Bluetooth, radio, dvd, audio in, etc.

Change the setting, click on SAVE, click on EXIT, then click on REBOOT, otherwise the settings will not be applied.

Play with the audio settings above to get all audio outputs to match in volume.

Change the system to 13 to get a peak of 4V output. This is high for a reason. You can only go lower if you use shielded RCAs. 100% of the idiots that install sound systems in cars get twisted RCAs. I am an audiophile and it is irritating to listen to idiots talk about how twisted is better.

Twisted pairs are for balanced systems (for example your computers modem and network card, thats why cat 5, 6 are twisted).

Shielded are used for UNbalanced systems, such as AUDIO PREAMP WIRE!!!!!!!!!!

I am not here to show my irritation on those people, but to give a break down of what my experience and problem fixing i have had with this unit.

I have a 3188, quad core, 16gb rom, 1gb ram variant of the 8" touch controls only.

First problem you will run into is that a regular air mouse/keyboard will not control the volume on this. Because of the design of the amp, volume up and down ONLY works with infra red remote control like the one included. Basically you will need to get something like the Mele F10 Deluxe to be able to control the volume as well as the android functions. Program the Infra Red part of the remote to copy the original remote and you are set.

Second problem with the unit is the touch screen. It is glitchy. The latest update 3/9/15 fixes this for the most part and makes the system more responsive. Boot time if you use the stock launcher is roughly 25 seconds. Which is not bad considering. The new update gives you the option for backup camera lines as well.

Third problem is grounding on this unit. The harness it comes with is very low quality although it does the job. The problem with it is that the connections are not 0 ohm. Usually they are around 2-10 ohm. This means that you have static generated ground feedback loop. There is no solution to this other than making sure the plugs are as tight as you can make them. This problem causes noise in the screen too when the background is almost white. Non perceivable for the most part, but i do notice it sometime.

Playing MP3 over usb is not bad, but you have to format the drive ON this head unit before taking it to your computer and copying stuff in it. Otherwise you will keep having that problem. DO NOT use a USB 3 drive for this. It will shut down the usb hub and cause reboots of the driver. Basically the problem you are experiencing.

ONLY 1 of the usb can handle the 3g connection. please refer to the label which is which, otherwise you will have issues with the drivers and things will not work properly.

No mater what, please UPDATE to the latest rom provided by the manufacturer. it fixes much of the stability and responsiveness issue. including some of the 3g connections.

Please remember that this units do NOT have a compass OR gyro sensor. ALLLLL navigation software do NOT know which direction you are facing. So you will not see the right image of the car in most of them. Orange arrow, red arrow, whatever the case.

Google maps is smart enough to use movement tracing to figure out direction. use that.

The DAC on this unit is terrible. I hate it. It can only decode up to 24khz files. you try 96khz and see what happens. But as far as head units go, audio quality is somewhere around the same level as lanzar.

It can do software decoding of flac files, but while you are playing music it will be glitchy. Sounds decent though with third party players.

In the settings you can go to GPS settings and set the volume for navigation directions. Type of mixing if you are playing music. you can stop the music and play directions then go back to music, or you can lower the music by however many points you chose and give directions and then increase the music again. All those settings are under GPS settings. Please look there. Some navigation apps also have their own controls within settings for those things. check those too.

There is no solution for the microphone. Install the external one that came with it somewhere convenient and that's it. Unless you want to do component soldering. I do not recommend it for someone that has not done this before.

Voice commands do NOT work reliably with tethered internet. Nothing can be done about this. It is google requiring a tested speed of 5mbps at the time of talking for it to work. Good luck.

Backup camera system is good on this. So is the Car DVR. They both work great.

The screen is too glossy and a pain to see in sunlight because of reflections. this also depends on installation position. i am speaking for the VW Jetta 2014 right now.

I am busy all the time, but if you have any questions please ask.

I hope this helps someone.