Dual USB ports, keep Front USB, Add Rear USB port, Carplay , Android Auto.
You will not see the messy data cable on the front panel, it looks more concise and neat.
Apple CarPlay wired keeps disconnecting
First of all, I apologize for the recent issues with the rear USB ports. I need to clarify that these issues only relate to the rear USB ports, not the front USB ports. Unless your phone cable is of poor quality.
If you are experiencing problems with your rear USB V4 version, there are several possibilities:
1. You are using a poor-quality phone cable. While the cable may appear thick and attractive, the internal copper wires are thin, resulting in high impedance and unstable data transmission. Therefore, I recommend using phone cables from the original manufacturer.
2. Due to non-standard design in some phone cables, the shielding wire is included in the impedance to ground design. I discovered this issue around late October 2025. I removed the soldering of the shielding wire on the RCD330 motherboard (removing the solder on the black wire or cutting the black wire (shield) from the 5-pin connector), leaving only the green, orange, blue, and brown wires soldered. Therefore, units ordered around the end of October with a rear USB port will not experience frequent disconnections due to this issue.
3. If you purchased the V1, V2, or V3 version of the rear USB port and are experiencing frequent interruptions, it means you're encountering the same problem described in point 2 above. Therefore, you need to unsolder the black wire of the shielded cable. Incidentally, the front USB ports on the V1, V2, and V3 versions are inoperable; only the rear USB ports work effectively.
4. Some customers use low-quality phone cables with poor conductivity and resistance to plugging and unplugging fatigue. Inferior products often use tin plating or a very thin gold layer at the USB port of the phone cable, which wears off and oxidizes quickly, leading to increased contact resistance, slower charging, or unstable transmission. Over time, this results in frequent interruptions. This explains why the rear USB port works stably for the first few months, but frequent interruptions occur with repeated plugging and unplugging of the USB phone cable.
5. The rear USB ports I selected (whether USB A/B/C) are all parts from the original Volkswagen factory and have Volkswagen and Audi part number markings. The USB port itself is reliable and shouldn't be the problem. However, frequent plugging and unplugging of the USB port (A/B/C) with a low-quality phone cable can cause oxidation of the four copper-colored metal contacts inside the port. A temporary fix is to use a lint-free cloth soaked in alcohol to clean the contacts with tweezers, removing the oxide layer or spots and restoring contact area.
6. If you have a Samsung or Google phone, they have very high requirements for stable operating voltage. Therefore, if you are using a phone cable to run wired Android Auto, it is recommended to plug it into the front USB port. Even with a front USB port, Samsung phones may experience instability when running wired Android Auto on other brands of car infotainment systems. You can easily find this information by searching for "Android Auto related issues" on Google.
7. The rear USB port was originally designed to better conceal the wireless CarPlay dongle. I've tried using other inexpensive and reliable wireless dongles, but there are so many manufacturers that I'm hesitant to abandon my original dongle supplier. I will try to reduce the cost of this dongle as soon as possible.
In short, choose a high-quality mobile phone cable (preferably from the original manufacturer). A high-quality connector will have a smooth plug-and-play experience with appropriate resistance, and will fit securely without any wobble after insertion. Inferior connectors may feel rough and loose. Inspect the inside of the connector; finely crafted contacts will be neatly arranged and have a uniform sheen.
Regarding your USB port issue, if you cannot resolve it, I am willing to responsibly accept your request to send the unit back to China, and I will repair the rear USB port soldering and related issues free of charge. I reiterate that all products I sell come with a one-year warranty. Even for customers past the warranty period, I will still provide free repairs as long as the cost is not high.