Now into the details

This firmware update for the ADI-2 Pro and ADI-2 DAC extends the Class Compliant compatibility. While all our Class Compliant devices work perfectly on Mac OS X, iOS and Linux, we are aware that in some other cases they don't. The ADI-2 DAC was the perfect candidate to change that. We got a Squeezebox Touch from a fellow RME user, and also examined why Windows 10 recognizes, but won't start the DAC as playback device (as you may know since Windows 10 1709 a UAC2 driver is part of the OS, so it should work right out of the box).

The new FPGA firmware 177 (Pro) and 17 (DAC) is the result:

- Logitech's Squeezebox Touch with EDO via USB, which did not show the ADI-2 DAC at all, now recognizes it and can use it as audio source via USB.

- Windows 10 now fully accepts the ADI-2 Pro and DAC as 2 channel record and 2 channel playback device. PCM up to 384 kHz, and DSD up to DSD256 are supported.

The latter has been tested with various software, among them Roon. While Roon supports ASIO it can also use Wasapi to change the sample rate automatically based on the sample rate of the currently played file. This also works when changing to DSD (set to 'DSD via DoP'), everything automagically within a mixed PCM/DSD playlist. And although Windows audio is limited to 384 kHz, DSD256 playback worked perfectly - which switches the ADI to 705.6/768 kHz sample rate.

So basically there is no driver installation necessary under Windows 10 anymore - unless you want to use ASIO and DIGICheck and the Firmware Update Tool. And please note, once the driver is installed the same restrictions apply as before: with WDM there is only one single sample rate available, no automatic sample rate switching from the application via WDM or Wasapi - only via ASIO.

There is some more going on with the Pro. When switched to CC mode Multi-channel Windows sees 6 input and 8 output channels. In our opinion Windows' UAC2 driver needs serious updates to work flawlessly in multichannel mode, the list of issues is long, and therefore we can not recommend using it in that mode right now. Basically WDM/DirectSound somehow works, but the more interesting Wasapi Exclusive and many other things in handling and configuration are not working at all.

Note that in case you want to try it yourself: Windows already fails to adapt between Multi-channel mode and Stereo mode. When changing the mode you have to enter the Device Manager, Audio, Video and Game controllers, select the ADI-2 Pro, click on 'Uninstall'. After that go to Actions - Scan for Hardware changes. The ADI-2 Pro is back and will work now in the new mode. Going back to the former mode - same procedure again.

We hope that other reported Class Compliant incompatibilites (for example some Synology NAS, Sony HAP-S1) are also solved by firmware 177/17. Please report back here. And in case of trouble with the ADI-2 Pro make sure it is in Stereo mode.

These changes will be ported to our other CC capable devices sequentially. I also would like to point out that the changes do not affect operation under Windows with WDM/ASIO driver, iOS or Mac OS X, with one exception: all I/O channels now have names, so under Mac OS X outputs 1 to 8 changed to Analog 1/2, Phones 3/4, AES and SPDIF (Windows does not read or use the channel names). Whether this makes changes necessary in existing DAW projects or not needs to be seen.

First user report received: Synology DS213+, which did not work with the ADI-2 DAC and firmware 11/20, now works using firmware 17/21.

Thanks for the firmware!

Firmware upgraded. Not more audio drop out. And now can work with Win 10 without driver.

Good job!

Thanks for the link, quite interesting. While I cannot exclude a fault on our side, Mac OS X working with both the old and new firmware in multi-channel mode clearly shows that it should work. Also the programmer of HQPlayer owns an ADI-2 Pro. I am pretty sure if that wouldn't work with Linux in general I would have been notified already.

The main problem here might be that multi-channel in CC mode just starts to get popular. See the mostly failing Windows 10 experience...

Just updated my ADI-2 DAC yesterday and it works great with my windows laptop! I am wondering if the further update would add support for the Android devices. I have a AK SP1000 and really want to connect it to the ADI-2. Right now it could only play DSD files through the ADI-2 so I guess adding support to PCM files wouldn't be difficult.

Yeah that's what bugs me. Usually it really should be working well on PCM if it could work on DSD. The thing is that when I plug my player in there, the sample rate of ADI2 just jumps to 768kHz directly, while on computers we could modify it with the software. Have you ever connected an Andriod phone to the ADI2? Are they working properly?

Unusual power on/off behaviour after firmware update of two ADI-2 PRO.

After usage in my system I switch the ADI-2 PRO off (red led power button) and then disconnect main power of the whole system.

If I connect main power again (next day) both ADI-2 PRO will power up (white led power button). That occurs very often (let's say 7 of 10) even if I wait about 20 seconds after power off of the ADI-2 PRO before main power disconnect.

Thanks. I think I always pushed the button only as long as it took to turn off the display, maybe a tiny bit longer.
How long would I have to push the button for the "emergency shutdown"?

I have checked what I was doing differently since the FW update.

I had activated "auto display off". So it is not possible to see the display turning off while pushing the power button because it is already off. I always waited for the LEDs to turn off and that is too long by far.

Please note that we just got notified about a bug in FPGA version 177, which adds distortion on the analog recording signal's left channel at sample rates 352.8 kHz and higher. If you don't use these sample rates for recording PCM or DSD you don't have to worry. Otherwise please go back to the former version 174 / 86 with the former Flash Update Tools:

https://archiv.rme-audio.de/download/fu … 174_86.zip

https://archiv.rme-audio.de/download/fu … 174_86.zip

An immediate update is not possible due to summer holidays, so it will take about two weeks until we can provide a fixed version of 177/87, which will have more changes that we finished working on already.