I purchased Carlinkit 3.0 adapter and it seems to be pretty useless. Installation process was rather straightforward. Unfortunately it lags awfully when playing Spotify music - sound stutters and freezes occasionally. Parallel using eg. Google Maps makes things even worse. Device upgrade hasn't improved anything. I had to return it to the seller. So, the topic is still open - I'm looking for a reliable and consistent CarPlay adapter that works with MBUX in my GLC.
I have recently install a Viseeo carplay dongle in my 2021 GLC, it was not cheap it usually sells for $300 but I was able to find it for $199 on amazon, I picked Viseeo because I have seen many reviews and it seems like the Viseeo received the best reviews.
It comes with two short cables a C to C and a C to B so it will work with any configuration your car may have. It was super easy to set up and worked the first try on both my iPhone and my wife's while sitting in the garage. The next day we were going to visit my son three hours away, I thought this would be a good test for the new upgrade. A mile way from home it stopped working and I couldn't get it to work again. When we got back from the weekend trip I tried it again but this time with an official Apple C to C cable and it has been working fine for the past week. I would like to point out the reason I tried the Apple cable is because when we purchased the car the dealer gave us a Mercedes cable and carplay would not work 90% of the time. On a hunch I tried my apple cable and it worked every time. When working you can't tell it's wireless very thing works the same and no delay.
So the conclusion at this point is I can't recommend this dongle just yet, one thing I have not tried yet is to use it with both paired phones in the car at the same time. When we went on the weekend trip both my phone and my wife's were in the car so I'm not sure yet if that was part of the problem. My wife has been using it for a week everyday and is very pleased.
Stay tuned for a update when I get a chance to drive around with both phones in the car.
UPDATE...We have been using the Viseeo dongle for a few weeks now so its time for an update on its performance. I am happy to report that it works as it should 95% of the time but every once in a while it will fail to connect. When it fails to connect I have to unplug the dongle and plug it back in which fixes the problem. I am happy to report that when it is connected to works perfectly with not delays or any other issues. The on thing I noticed is that on short trips it is a dream not having to connect my phone to a cable but on long trips it just drains the phone battery and I end up connecting anyway to keep the battery charged. Another problem I have had is only one phone will connect to MBUX when using the dongle.
In conclusion I can recommend the Viseeo dongle if you don't mind unplugging it once in a while and only one phone connected to the MBUX