ZedZed

The factory system is only fiber optic on Bose systems, which not everyone has. In my wife's non-Bose Cayman the sound is definitely better since installing the Android HU. Also, the EQ is way better, so there is also the opportunity of fine-tuning the sound, which doesn't exist in the outdated PCM.

In my Panamera, which has Bose, I am not hearing any significant differences in sound TBH. (I am an experienced listener of very high quality audio systems). I am of the view that a DAD additional conversion makes negligible practical differences, even in high-end systems, let alone car systems.

But even if the sound from these units did suffer somewhat, that is more than compensated for by all the up-to-date features these units bring. Even Porsche are of the view that PCM 3.1 is not a satisfactory infotainment solution any more, which is why they have junked it (at last).

ZedZed

That is correct. Roman got that part wrong. It's possible that the op amps in the new HU are superior to those in the PCM 3.1. In fact, given how old (and cheap - to make, not to buy!) the PCM 3.1 is, it would be surprising if that weren't the case.

ZedZed

Yes, the PCM is so thoroughly outdated that this is likely to be the reason for what you are hearing. I had a brand-new pickup that had way better SQ than my Panamera/PCM 3.1.

jadski

Update: Wireless CarPlay has been working great. It typically boots up and loads super fast. It was occasionally kicking back to the native android mode; but I believe I have solved that problem. I think it was a setting on the vivid launcher to automatically go back to the Home Screen after a period of time.

so far I am very pleased with the unit and it’s a huge upgrade.

my lane change assist error went away and everything seems to be working fine.

The rear speakers are not playing any sound. I have messed with the equalizer/fader settings ad nauseum and cannot get any sound. I have Bose and used the most box. My daughters complain a little bit but I have great sound in the front. If anyone has any suggestions about the rear, let me know. Probably not as much of an issue in a 911. Kinda annoying in the Macan

bmxtreme

Can you try connect that Amp Con wire to the 12v wire like how the non-bose system would do it and see if it it will give you rear audio?

​

ZedZed

I had a similar problem in my Panamera. I did eventually find a solution and now I have sound from the rear speakers, but it is just a copy of the sound to the front speakers (that is, it is not any form of 'surround sound'. The problem is, I did this over a year ago and cannot now remember how I did it. I realise that this isn't much help to you, but am relaying it just to show that it can be done. From memory, I had to go into the DSP settings screen, and then dive into the various tabs and mess with all the faders and settings there. I remember noticing that as I directed sound to the rear I could not send ALL the sound to the rear, like a fader will usually do. But I got enough to the rear to make it obvious to rear seat passengers. Of course, all of these HUs can have different software variations and what might work for one might not work for another. Next time I am in my car I will try to find the exact settings I changed and will report back.

andy2111

Not sure what the latest version of CarLink is that the head unit itself will update to, but here's a link to the latest .apk on XDA (only install this if you know what you are doing!)

Question - Any Car Link Update? | Page 18 | XDA Forums

ratt359

I'd suggest that updates to "system apps" like CarLink only be done from the proprietary "App Store" - and only where there's a problem to solve. Don't assume that latest is better!

Latest release of CarLink for the CHSTEK 7862 via this channel is 2.23.1223.1104.

In the same repository as the guide, I'm keeping copies of the system app APKs that are pulled down by the "App Store" under "03. Software > CHSTEK updates", mainly to facilitate roll-back if ever required.

ZedZed

While I agree with the general caution about not using apks unless you know what you are doing, Carlink isn't a 'system app' as such. It is just a bridge between the head unit and a phone. It's functionally the same as Zlink, which I have updated a few times with no issues arising. Carlink is like any other Android app, but just not available on the Google Play Store (although may well be available on other app stores such as Aurora). As I have said before, if Carlink is causing issues, there's no reason why anyone shouldn't give Zlink a trial - they both do the same job.

If you are going to use either app, you will need to know about installing apks, and be sure to download them from reliable sites such as apkMirror.

drawz

I noticed @jadski has Carlink 2.24.0418.1646 in a screenshot. The 24.0418 is probably a date code. Of course there's no changelog to be found, but hopefully bug fixes. *edit - oops just saw the link to XDA with 2.24.0611.1557. I need to try updating from the FYT app store again or will sideload this.

For rear speaker sound - I believe the fader gets stuck on whatever the PCM had set before being removed. It's possible that's your issue. The head unit fader won't work because it only outputs a stereo signal.

ZedZed

You are right that the HU only outputs a 2ch (stereo) signal, but it can still be output to more than 2 speakers. It will only be a copy in the second pair of speakers of course, but that it is what it was in the original PCM too, unless you used the (awful)) pseudo-surround mode. I haven't had chance yet to try to rediscover how I got sound from my rear Panamera speakers, but I will have a look tomorrow and, if I can recall what I did, will report back. It's not a great solution but it works (kinda). Better than no sound at all from the back anyway. Of course, since my HU in the Panamera is a different type (wdescreen) different maker (Zwnav) and quite possibly different (rooted) software, whatever I did may still not work on the CHSTEK units.

ZedZed

^^^^
It should be possible, with a bit of jiggery-pokery, to wire the front output to the rear output, stick a cheap potentiometer in somewhere (say under the dash or in the glove box) and create a rear speaker setup. Once a decent balance has been achieved between front and rear, the pot shouldn't need to be touched again, so can be hidden away. The caution would be that if the speakers are wired in parallel, then there is a halving of impedance to both sets. With 8 ohm speakers, this would give a total load impedance of 4 ohms for each speaker . This should be OK for most modern amps, but I would recommend checking the impedance of the existing speakers and the rating of the existing amp. If the original speakers are already 4 ohm, then dropping to 2 ohm might be more than the amp is happy with. Having said that, if the speakers are wired in series, then this should be safe - two 4 ohm speakers in series, for example, makes a total load impedance of 8 ohms (or two 2 ohm speakers = total load of 4 ohms) which most amps should be OK with. Bear in mind that changing the overall impedance will increase or decrease the power output of the amp.Parallel wiring = increased output power and Series winding = decreased output power. So a Series setup might result in insufficient amp grunt (although probably of no concern in a car setup for most).

For most people, these suggestions are probably not worth the trouble - esp. those with 2 seater cars. For those with 4 seater cars, it may be worthwhile if you regularly carry back seat passengers who want music. But in my own use scenario, if it's kids in the back seats, they are much happier using their phone to stream content of their choice. This has the knock-on benefit that the driver doesn't have to listen to Taylor Swift at max volume for hours on end

andy2111

Could the suggestion that the rear fader settings from the last use of the PCM be relevant here? Maybe if the rears had zero volume before the PCM was removed it might account for the current problem?

Requires a quick refit of the PCM to try to fix it though....

StanfordBear

With my CHSTEK 7862e arriving next week, I just wanted to clarify whether anyone who has installed it has been getting sound to the rear speakers without any additional type of mod? My current PCM fader settings are set to have sound from the rear Bose speakers.

andy2111

I'll leave someone with Bose answer that for you, but as a precaution make sure you max out the volume to front and rear speakers before disconnecting your PCM