HDMI issue with MacBook Air M1 using USB-C Digital AV Multiport Adapter with projector

usagora · Mar 28, 2021

I'm experiencing an odd issue here. When I connect my MBA M1 to my Epson 485W projector via HDMI using the (not-so-cheap) Apple USB-C Digital AV Multiport Adapter, I'm experiencing this:

I've tried restarting (projector and MBA) and using a different HDMI cable. I've also tried with another Epson projector with the same result. Here's the weird thing, though. It works perfectly fine with my 60" LG 4K TV using the same HDMI cables. So this would indicate it's neither a faulty adapter nor faulty cable. So you'd conclude it must be something wrong with the HDMI bus on the projector, right? No, because it works perfectly fine with both an Apple TV and my 2012 MBA using an HDMI to TB2 adapter. So the only thing I can think of is it's some sort of incompatibility with the HDMI bus on Epson projectors and the HDMI-to-USB-C adapter. Is there something unique to HDMI bus on a projector vs. a TV that would be causing this?

FWIW, I'm also connecting to the same projector via VGA using the Apple USB-C VGA Multiport Adapter and it works flawlessly.

I've just ordered this Anker USB C to HDMI Adapter and will report back if I have the same issue with it. If I DON'T, then I would be wondering if it's an issue of single vs. multi-port adapters when hooking to a projector.

EDIT: Here's another interesting experiment I just did. I have both a VGA-to-HDMI adapter (third party) and a HDMI-to-TB2 adapter (third party). When I connect the projector to my MBA M1 using a VGA cable, the VGA-to-HDMI adapter, and the Apple USB-C Digital AV Multiport Adapter, I get no video signal. However, if I connect the projector to my 2012 MBA using a VGA cable, the VGA-to-HDMI adapter, and the HDMI-to-TB2 adapter, I get a video signal. So strange...

Lifeisabeach · Mar 29, 2021

I think the problem may be that you are using a USB-C to HDMI adapter. Try Thunderbolt 3 to HDMI instead. Yes, Thunderbolt 3 and USB-C have the same connector and are cross-compatible to a point, but Thunderbolt 3 is, for lack of a better explanation at the moment, a "higher-level" spec. It's backwards-compatible with USB but otherwise is a more capable standard. Just to illustrate one example that I've encountered. I needed to boot my MacBook Air into Target Disk Mode and connect it to my iMac. That mode is only supported with Thunderbolt on these models, not USB. I had to buy a Thunderbolt 3 cable just for this task despite a handful of USB-C cables laying around that "look" the same but couldn't do the job.

usagora · Mar 29, 2021

Lifeisabeach said:
I think the problem may be that you are using a USB-C to HDMI adapter. Try Thunderbolt 3 to HDMI instead. Yes, Thunderbolt 3 and USB-C have the same connector and are cross-compatible to a point, but Thunderbolt 3 is, for lack of a better explanation at the moment, a "higher-level" spec. It's backwards-compatible with USB but otherwise is a more capable standard. Just to illustrate one example that I've encountered. I needed to boot my MacBook Air into Target Disk Mode and connect it to my iMac. That mode is only supported with Thunderbolt on these models, not USB. I had to buy a Thunderbolt 3 cable just for this task despite a handful of USB-C cables laying around that "look" the same but couldn't do the job.

Interesting thought, but that raises other questions if true. Why would the Apple USB-C Digital AV Multiport Adapter work with my 4k (3840x2160) TV but not a WXGA (1280x800) projector? You'd think a 4k display device would require the higher standard. And why would Apple sell such an adapter if it didn't work with projectors, which are VERY commonly used with their notebooks? In fact, the product page even says, "Requires an HDMI cable (sold separately) for connection to your TV or projector. Supports both video and audio output." They don't sell a "HDMI to Thunderbolt 3" adapter...only one I see on their site is this third-party one which is very expensive and overkill). When I search on Amazon for "thunderbolt 3 hdmi" the vast majority of the results say USB-C and "Thunderbolt 3 compatible". Here's one that simply says "Thunderbolt 3" but it's $90.00 (yikes!)

I think I'll wait to try the Anker adapter that I ordered before spending even more money on this. I'll let you guys know (should arrive Tuesday). If it doesn't work, I think I'll call Apple support before spending nearly $100 on another adapter - will also let you guys know what they say if it comes to that.

usagora · Mar 30, 2021

Well, guess what? The Anker USB C to HDMI Adapter I ordered from Amazon arrived today, and works perfectly, so the Apple USB-C Digital AV Multiport Adapter is clearly faulty or at best not compatible with (Epson?) projectors. So strange. I'm going to call the Apple Store tomorrow to see if they can exchange it.

Jim40 · Apr 2, 2021

I've had the same problem streaming video from my 2019 MacBook Air to a HDMI input on my TV which has 4 HDMI inputs. When I've finished this reply, I'm ordering an Anker from Amazon.
Thanks for the advice. Will keep you posted.

usagora · Apr 2, 2021

Jim40 said:
I've had the same problem streaming video from my 2019 MacBook Air to a HDMI input on my TV which has 4 HDMI inputs. When I've finished this reply, I'm ordering an Anker from Amazon.
Thanks for the advice. Will keep you posted.

Glad this could be of help! Hopefully the Anker works for you as well. Strange, though, how it works for me with the TV but not you. I thought HDMI was a standard that wouldn't change from device to device, but apparently it does (or both our adapters are faulty in different ways).

Jim40 · Apr 8, 2021

Got the Anker HDMI to USB connector but still doesn't work. After a bit of reading up I was able to install the YouTube app on my TV (It's a Smart TV with lots of Apps I can use)
It is now working fine and I can watch any You Tube Music videos wirelessly on my TV. Also downloaded the Desk App for YouTube and can use the Anker I bought to connect my MacBook Pro Retina and with a USB 2, but cannot get a USB C lead with a HDMI socket on the other en to work. I'm happy enough with what I've achieved with help given here. But I was always taught in my early days of Mac (1992 to present) that if I had a problem and eventually sorted it, just be happy I've got it to work and not critically analyse what I'd done.

Thanks guys for your help. Didn't achieve my original problem but I have what I wanted.

usagora · Apr 8, 2021

Jim40 said:
Got the Anker HDMI to USB connector but still doesn't work.

That's very odd that neither adapter worked for you for a simple connection to a TV. When you connected via the Anker adapter, did you get an unstable image or no image at all?

Glad you've found a workaround, though.

Jim40 · Apr 9, 2021

No image whatsoever !

Jim