I am getting a horrible static noise when I connect my Zenfone 9 to my car with 3.5mm cable. This is not happening when I use my iPhone mini 12 with a 3.5mm converter. First time buying an Asus phone but this makes me think about the general quality concept of Asus. I can see there are many other users having the exact same issue but there is no solution provided from Asus. Not good.
Yes, I have checked the possible debris but it seems like there is no dirt or debris in the Jack.
on the other hand if you check the forum you can easily understand that this is a common issue starting from even earlier models. At that point i can only think this is a long lasting quality issue with Asus. It is a shame.
You cound try using the USB-C out with an adapter - provided the adapter has a DAC. The phone automatically routes audio to USB and my ZF9 at least works with a DAC-enabled adapter as well (and regular wired headphones).
Secondly, the 3.5mm outputs on phones are specced to provide proper audio output under specific conditions. With the Zenfones I have used so far it works very well with a myriad wired headphones as well as a couple of BT speakers that also take a wired input. What your car (or cable-car combo) does with the input provided by the Zenfone's audio jack is not as easy as "it's Asus's fault".
I totally understand your point but i still insist that this has been bothering so many people including me and i really think that this could be fixable by some design changes by now. If I am required to use a converter then why there is a headphone jack on my phone? It seems like no one from dev/design team is watching this forum.
Anyways i fixed it by buying a ground loop isolator. Thank you for your opinion.