Airport Express Firmware 7.8 will not stream Audible content

I’m having this exact problem. Non-Audible content seems to work fine. I tried playing some non-DRM tracks, and they were OK. I still have a few protected AAC files, and when I went to play them, I got this error:

But I re-checked the device, and it played OK.

I’m going to go back to 7.6.9 until I find a fix.

For what it's worth.......things are working just fine on two AirPort Express 802.11n devices that were updated to Firmware 7.8.

Try reinstalling the firmware again with your Mac connected to the LAN <--> port on the Express using an Ethernet cable. Be sure to turn off the WiFi on the Mac when/if you decide to do this.

Ok, just set up both a 1st & 2nd gen AirPort Express base stations. I then streamed an audiobook (Chase - Dean Koontz, purchased from the iTunes Store) from iTunes (v12.8.0.150) on my 2014 Mac mini (macOS High Sierra 10.13.6). With both base stations selected, I didn't get any errors streaming to either. I can also stream successfully to either station individually. The 1st gen is running 7.6.9 & the 2nd, 7.8.

I only have these two remaining Express base stations to test with. I made sure that no software firewalls were running on my mini and that it was configured for IPv6 Link-only mode. All connections between the iTunes host and the base stations were Ethernet through multiple Ubiquiti managed Ethernet switches.

same for me, I decided to roll down the 7.6.9 and all fixed for me

to do it:

Open Airport Utility

select the Airport Express you want to downgrade (I have 4x)

and Hold down ALT key when selecting the firmware 7.8

a dropdown list will appear

just select the 7.6.9

I contacted Apple about this late last week. I started in a chat, which then went to a call, which then went to a call with a senior advisor. After copying of logs and screenshots and so forth, it’s now apparently in the hands of the engineers and I expect to speak to someone again some time next week.

I also contacted Audible, because what the ****. Audible’s support people don’t seem to be nearly as good at asking questions (or, indeed, properly understanding the answers) as Apple’s, and the end result was the advice that I should contact Apple. But one interesting -- but probably unhelpful -- thing: I download Audible files in the “Enhanced” format, which do the play-without-sound thing. I tried downloading a file in “Format 4,” and it didn’t play at all. It just stopped immediately as soon as I clicked the play button.

It was just released today, so it will be difficult to know if this is an actual problem, and if so, whether or not, will release an update to resolve it.

I had a chance to upgrade the firmware on my AX2 with v7.8 and I can confirm Bob's comments that I had no issue streaming to it including from an Audible content source.

For what it’s worth: based on this, I tried deauthorizing and reauthorizing iTunes with Audible. No change.