[Android Head-Units] HVB83:
This thread was started to collect the information available on the Ownice C500 in a couple of posts. Please feel free to provide your input and I'll try to add your suggestions to the OP, so that we hopefully end up with a centralised overview of this system.

General

First off, the specs:

http://www.ownice.com/Pro_Head Unit for 2din universal_449.html

I've heard rumours of 8-core units coming along?

The unit called C500+ has been released for a limited amount of cars in comparison to the C500:

http://www.ownice.com/Pro_Head Unit_450.html

Main differences seem to be:

- Octacore CPU (Cortex A53 clocked @ 1.6ghz as in the 4-core version);

- 32GB ROM;

- Anti-glare touchscreen, improving readability in sunlight;

- According to Ownice representatives the rear-cam design flaw has been resolved, but so far nobody on this forum has confirmed this.

Confirmed items working (which are known to cause issues on other units):

- OBD-connection through bluetooth, including Torque Pro and Dashcommander are fully working;

- Apps sensitive to serial length, like navigation apps as Tomtom and Navignon;

- Music player buttons on front-panel working on Poweramp by default, no need to root the unit in order to be able to reassign the buttons;

- Internal microphone can be disabled when using an external microphone, vastly improving sound-quality during calls. Be aware that you need to specifically ask for Ownice to provide you with a jumper-module when ordering your headunit, or to connect the wires yourself. It should be plugged into the following connection: https://xdaforums.com/attachment.php?attachmentid=4091227&d=1490655262, the red stripe shows where the jumper should be connected.

Known bugs and flaws:

- Limited RDS-support, with the unit only showing the station program category, not the station name.

- Rear camera does not work until the unit has fully booted (which takes approx. 30s). By setting the shutdown delay, the unit will work op to 60 minutes after you've turned off the ignition. So getting groceries should be possible with immediate rear cam functionality.

- Rear camera image for some people seems to provide problems with washed-out picture quality. It seems not everybody is affected by this issue, the extend of the problem unclear and the cause remains unclear. On another forum, people have resolved the issue by soldering a 100ohm resistor in the signal cable of the camera:

https://dl.xda-developers.com/4/0/8/0/2/0/2/9575874.png?key=gBSDLtr0nodVYAPPpdlxAw&ts=1489908543

- Limited functionality equaliser. This can be circumvented by using Viper4Android to improve overall sound quality. If you want to avoid having to root your system and to improve the sound quality of the system, an even better alternative would be to use a DSP like http://mosconi-system.it/product/gladen-dsp-4to6/

- DAB-package is not working. No solution found at the moment.

So what's the verdict, is it worth considering?

That's up to personal preference and experience. None of these Chinese units are bugfree on a level that you would for instance expect from a Kenwood or Sony unit (but to be fair, they don't provide us with this kind of kit, for a reason). Ownice however has released several firmware updates, squashing several bugs in the process. They have therefor shown that they are more serious than most competitors in providing some sort of aftersales service to their clients. Only Joying seems to be on the same level or even higher.

I've had one of these Chinese units before and my rear cam quality is not better or worse on this unit than it was on the previous one. You shouldn't expect HD-quality, but neither is the overly expensive cam on my 2016 lease car. For preventing to bump into objects behind you, it is perfectly fine though and you don't need it for anything more. Whether or not you can live with RDS-support missing and the camera taking longer to show up, is up to you.

The software seems stable and very responsive, with no crashes during normal use. This was also not the case on my previous unit, where satnav apps (if you could open them, because many of them would not open due to software issues anyway!) felt clunky and using different launchers could make the unit almost unusable.

So far it seems these are about the issues you'll find with this unit. If you can live with those, the C500 will buy you a solid unit for everyday use.

Basic tips & tweaks

Wiring and connection scheme

Your wiring and devices can be connected as follows:

Make sure your connect the 4G-antenna and GPS-antenna to the right connector. Failure to do so won't get noticed at first, because you will get the signals to some extend. It will however lead to frequent reboots of the unit and cause the GPS-signal to be very unstable.

Where can I find firmware updates?

Please be aware that there have been reports of devices being bricked even though the procedure was apparently followed correctly, in which case your unit needs to be returned to Ownice or you will need to install a new board! Ownice will release a video tutorial to show the proper procedure for flashing new firmware.

https://xdaforums.com/android-auto/android-head-units/ownice-c500-firmware-updates-t3560984

After downloading the steps should be as follows:

- Make sure your car battery is full or connect a charger!

- Unzip files into root of your SD-card or USB flashdrive;

- Unless you are absolutely sure your car doesn't cut out ACC-power after a few minutes of not having been started, please start your car now. Re-flash procedure might be stopped if this happens, resulting in a bricked device;

- Connect the card or stick with your C500 and restart the C500;

- Firmware update should start automatically.

My device got bricked, is there anything I can do?

For now, there is no known procedure to unbrick your device. Ownice is shipping replacement boards to end-users if you are brave enough to do the replacement yourself. If you would like them to do the works, then you need to ship your unit back to China.

I often hear about the "1260 settings menu", what is it and how can I enter this?

This is a menu which allows you to change the more advanced settings. Please be aware, this is not intended for end-user changes and some of these settings might render features of your unit non-functional and cause other kinds of strange behaviour! You can access this menu through apps / settings / software version. There is a small cogwheel in the top right corner. Press it and enter "1260 + ok".

How do I access the "Engineer mode"?

Step 1: open "Phone" app: https://www.dropbox.com/s/pw7rdg0uuqj484h/20170324_174139_resized.jpg?dl=0

Step 2: press the dial pad: https://www.dropbox.com/s/10keoommpj3n4iw/20170324_174152_resized.jpg?dl=0

Step 3: enter *#*#3646633#*#* https://www.dropbox.com/s/mlc8aq2ir49aga0/20170324_174256_resized.jpg?dl=0

You're now in the engineer mode. Please be careful not to change any values for which you're not sure what they do, as this could potentially break your unit!

How can I change the boot logo?

Under apps / settings / general / boot logo you can access the boot menu. Enter "9999 + ok" and you can set the boot logo according to your liking.

I updated firmware to 3/24 latest version and now when I try to get to Play Store and other apps, *I get this black notice on screen that tells me not to watch while driving. *I can not set up my apps and system with this bug. *Is there a fix?

Either connect the "Brake" wire to ground, or in the settings menu, set "Brake" value to 1.

I cannot export files from my DVR-cam

You need to have ESFile Explorer loaded. Before you go o into CarDVR, turn of the cam video. Next, go into playback. ESFile Explorer pops up and at the bottom you should see the USB for the DVR camera. There you will find all videos recorded. Select the recording you would like to export and copy it to the source of your liking.

Can the microphone sensitivity be adjusted?

Yes, inside the 1260-menu there is a volume setting for the mic, which is around 30 as standard. Set it to 60-64 and see if that improves the quality for the other party. If you get acoustic feedback, you've set the volume too high and you should tone it down. It depends on all kinds of factors, so there is no one setting fits all here.

There is also an advanced setting in the engineer mode available to improve speech quality further, which will be discussed later.

Advanced tweaks

How-to root:

https://xdaforums.com/android-auto/android-head-units/ownice-c500-root-t3558760

What options are available after applying root?

For one you'll have the possibility to install and use apps like Viper4Android and modify system-files. I don't think Xposed and the likes are working right now, so combined with the features the C500-platform offers already, the root option opens up a wide range of opportunities for the future, but right now the added value seems limited for the average user.

How-to install Viper4Android:

https://xdaforums.com/android-auto/android-head-units/ownice-c500-how-bettering-sound-root-t3563836

DAC-support:

What's an USB DAC?

Some of you might wonder why you would need an external DAC, isn't that something for those geeky bearded guys in their 60s who call themselves audiophiles and gather on sunny Sunday afternoons, listening to overly expensive audio systems together with other geeky bearded guys in their 60s?

Not really.

The digital information from your unit needs to be converted into an analog source in order for your amplifier to drive the magnets in your speakers. This signal to your amplifier can usually be something between 2v to 8v, but in our units it's 2v. That is, with maximum signal strength. If you want to be able to control the volume and with poor tracks, you usually end up with 0,5v to 1v under "normal" listening circumstances. It's not hard to imagine any kind of electromagnetic interference (EMI) inside your unit will have an effect on the quality from the pre-outs. These interferences all add to the noise floor and with such a low voltage as your source inside a very small metal box, it's not hard to imagine noise is added to the point where it's becoming annoying quickly. It's explained in more detail here.

To add to that, the DAC inside these Chinese units is simply poor. This is an issue that all brands suffer from. They are not aimed at sound quality.

Adding a DAC will take out many issues with EMI. I am sure you don't have to be an audiophile to experience the quality boost you will get from this addition. Really, if I had to choose between loosing the DSP or loosing the external DAC, I'd have a hard time since I wouldn't really want to do without either of them, but in the end I'd think I'd rather loose the DSP. And at $30, I'd say it's really a no-brainer.

Sounds great, how can I install it?

DAC-support is possible and has successfully been tested in combination with a Behringer UCA202 USB DAC . There might be better units out there, but this unit has a very good price vs. quality ratio, as you can see in this in-depth review. Please report back in case you tested other DACs with success and we'll add them here.

With the changes below, volume control is working out of the box with apps like Poweramp, Youtube, Google Music and Tomtom. Nav cues are working as should, including soft mute of the music playing, etc.

The only drawback for now is, that the handsfree audio is no longer available. It appears this is due to the configuration in the output descriptions below and should be solvable.

Steps to be taken:

1: Root your unit

2: Replace the /system/etc/audio_policy.conf with the following code:

# Global configuration section: lists input and output devices always present on the device
# as well as the output device selected by default.
# Devices are designated by a string that corresponds to the enum in audio.h

global_configuration {
attached_output_devices AUDIO_DEVICE_OUT_SPEAKER
default_output_device AUDIO_DEVICE_OUT_SPEAKER
attached_input_devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_BACK_MIC|AUDIO_DEVICE_IN_VOICE_CALL|AUDIO_DEVICE_IN_REMOTE_SUBMIX|AUDIO_DEVICE_IN_BLUETOOTH_A2DP
}

# audio hardware module section: contains descriptors for all audio hw modules present on the
# device. Each hw module node is named after the corresponding hw module library base name.
# For instance, "primary" corresponds to audio.primary.<device>.so.
# The "primary" module is mandatory and must include at least one output with
# AUDIO_OUTPUT_FLAG_PRIMARY flag.
# Each module descriptor contains one or more output profile descriptors and zero or more
# input profile descriptors. Each profile lists all the parameters supported by a given output
# or input stream category.
# The "channel_masks", "formats", "devices" and "flags" are specified using strings corresponding
# to enums in audio.h and audio_policy.h. They are concatenated by use of "|" without space or "\n".

audio_hw_modules {
primary {
outputs {
primary {
sampling_rates 48000 | 44100
channel_masks AUDIO_CHANNEL_OUT_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL|AUDIO_DEVICE_OUT_FM
flags AUDIO_OUTPUT_FLAG_PRIMARY
}
}
inputs {
primary {
sampling_rates 48000
channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_VOICE_UPLINK|AUIDIO_CHANNEL_IN_VOICE_DNLINK|AUDIO_CHANNEL_IN_VOICE_UPLINK_DNLINK
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_BLUETOOTH_SCO_HEADSET|AUDIO_DEVICE_IN_WIRED_HEADSET|AUDIO_DEVICE_IN_BACK_MIC|AUDIO_DEVICE_IN_FM_RX|AUDIO_DEVICE_IN_VOICE_CALL
}
}
}
a2dp {
outputs {
a2dp {
sampling_rates 44100
channel_masks AUDIO_CHANNEL_OUT_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_OUT_ALL_A2DP
}
}
inputs {
primary {
sampling_rates 48000 | 44100
channel_masks AUDIO_CHANNEL_IN_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_IN_BLUETOOTH_A2DP
}
}
}
usb {
outputs {
usb_accessory {
sampling_rates 48000
channel_masks AUDIO_CHANNEL_OUT_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_OUT_USB_ACCESSORY
}
usb_device {
sampling_rates 48000
channel_masks AUDIO_CHANNEL_OUT_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_OUT_USB_DEVICE
}
}
inputs {
usb_device {
sampling_rates dynamic
channel_masks dynamic
formats dynamic
devices AUDIO_DEVICE_IN_USB_DEVICE
}
}
}
r_submix {
outputs {
submix {
sampling_rates 48000
channel_masks AUDIO_CHANNEL_OUT_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_OUT_REMOTE_SUBMIX
}
}
inputs {
submix {
sampling_rates 48000
channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO
formats AUDIO_FORMAT_PCM_16_BIT
devices AUDIO_DEVICE_IN_REMOTE_SUBMIX
}
}
}
}

To be done

As said, audio output from the handsfree unit isn't working. This is probably related to the selected output device in the above config file.

Apart from that, USB DAC is working.

Unknowns

Can I reassign front-panel buttons to non-standard apps?

Does not seem possible at the moment.

How can I remove the PIN-request at start-up?

Some people have claimed removing the PIN-request is possible through the engineer mode, but this has not been confirmed as of yet. For now, removing the PIN from the SIM seems the easiest, although a bit risky if it's not a flatrate/pre-paid plan.

This post will be extended in the coming days. Please feel free to contribute in the mean time!