my guess is that the expansion card, like the built in port, only uses a TRRS jack, meaning there are two conductors for audio output from the laptop, but only a single conductor for audio input to the laptop, meaning that you will only be able to get the mono input you are seeing without switching to a usb-c source.
Note: I do not have the audio expansion card, so this is just a guess. messaging support is the best way to get the official answer to this question.
I have not done any testing with line in, however, might worth updating the kernel to something a bit newer. There are other tweaks that we tested here as well on the linked pages at the url below.
I tried everything listed in the installation guide, without success. A screenshot of the PulseAudio Configuation tab shown the problem. In the profile dropdown menu for the audio expansion card with the 3,5-mm-plug connected only the options “Analog Stereo-Ausgabe” (Analog Stereo Output), “Digital Stereo (IEC958)-Ausgabe” (Digital Stereo (IEC958) Output), and “Aus” (Off) show up. No Option for “Analog Stereo Input” is shown, although according to the marketplace entry Audio-In should be supported. Definitely no idea.
Update: With a usual 4-pole headset connected, the dropdown menu offers the following possibilities. I conclude, that using the input function requires a 4-pole connector and only supports mono audio.
This is not what I expected and for what I paid 20 € for the expansion card + 30 € (!) for the shipment.
It seems I have to buy a usual audio-USB-grabber instead.
Aren’t all normal TRRS / 4-pole 3.5mm headset jacks mono microphone? Not sure how would you even support standard stereo + mic headsets and at the same time support stereo mics.
I believe the reason the Audio expansion card was made is mostly that it will be needed for the Framework-16. But it also provides better audio than the built-in Framework-13 jack.
TRRS is generally stereo output mono input, yes.
My comment here has more information in the specific context of the internal audio on the FW13:
I vaguely recall that a number of years ago, some Macs had switchable 3.5mm audio ports, such that, I think, you could set the interface, for example, to have TRS stereo input and no output, and set line-in vs mic-in; these also had optical input/output on the same port; at the time Apple was still trying to cater to creative fields and a featureful audio interface was a selling point. But a feature like this would require specific support from the chipset (switching between input and output on the same line). At least with the internal FW13 interface, that support isn’t there.
In general, my understanding is that the 3.5mm expansion card is not really significantly better than the internal audio interface of the FW13, at least in terms of features. I don’t see any indication that it would be arranged differently, as its primary motivation is to have a 3.5mm port on the FW16.
It is a bit disappointing in this regard, and there would be room for a more featureful audio expansion card, but the one Framework offers isn’t.
Have you checked at a lower level here, eg, with alsamixer? In some cases there are settings on the card that are not really shown in pipewire/pulseaudio, like mic boost.
Why would expect it to have stereo input it is pretty clearly an alternative to the fixed input for the 16"
I can understand your issue especially after the cost, but sadly there was no indication is was any sort of upgrade.
I’d love to have a stereo input but that may have to be via a USB C port
Your note that is new is really only that it wasn’t available before the 16" not that it was any sort of upgrade and their was no indication that the 16" was any different.
Sad but that’s what I imagined and didn’t even think of asking if it would do stereo.
Can we get a confirmation from Framework that the new audio expansion card is mono input only? Could you find out @Matt_Hartley? I had also assumed it was a 3.5mm trs stereo input, but luckily I haven’t purchased yet.
The product page description reads:
The Audio Expansion Card contains a 3.5mm headphone jack, which supports audio input and output. This Expansion Card provides increased dynamic range and improved signal to noise ratio in comparison to the Framework Laptop 13 built-in audio jack.
I think it would be really helpful to update that description to make clear the output is stereo and input is mono - if that’s the case. Product descriptions shouldn’t really allow any room for assumptions either way. Technical specifications would stop any further confusion or disappointment and the hassle of increased support and return requests.
Edit: Also I think it’s worth pointing out that this expansion card isn’t being sold as 16" laptop specific. Increased dynamic range and lower signal to noise ratio is an improvement over the 13" laptops soldered audio output and for some people that’s a reason to buy.
That’s very presumptuous. 
Clearly if it’s not in the specs why assume ?
So it seems waiting at least saved yourself the embarrassment of buying without knowing.
Sad but true, who wouldn’t want a stereo input, as was common 
Why assume the output is stereo? That’s not in the specs either.
Like I said in my post, there are no specifications in the description at all. And no specifications allows for assumptions to be made both ways. You expected the input was mono, I expected it was stereo - it’s a coin toss.
Adding tech specs to the marketplace product page removes any possibility of a customer making assumptions and ensures they make an informed decision before purchase.
There’s also this thread
I agree to fyoosh that precise specifications in the marketplace are recommended.
Besides that: Already before ordering the framebook itself I asked whether the built-in jack was also for stereo input, and this was confirmed. Finding out it did not work led me to discuss this issue with the support, without final result.
So I had the idea the expansion card was also created to tackle this issue, and I read the description in the marketplace the same way as fyoosh does.
I think the proper solution would be to offer an audio expansion card with all those features a desktop pc has: TRS line in, line out and mic in.
What is particularly frustrating about this is that, unlike manufacturers who simply don’t give precise specs, Framework often does, to the point of individual chips, but puts them in blog posts, in employee forum responses, and in files on Github, while the Marketplace often gives little or no specific information. I’m certainly not criticizing the disclosure of the information elsewhere, but it seems like it would be more organized to put it in the Marketplace too. I feel like some parts of Framework’s target purchasers would find the information quite useful, and many others, even if it wasn’t useful to them, would appreciate it being there.
That’s very disappointing. I think the problem here, as I discussed in the other thread, is that the chipset does support stereo input generally (ie, it has more than one ADC), and there is stereo input from the internal microphone, but the wiring and switching mechanism to enable stereo input from the 3.5mm jack is not there. Support should understand the difference between these two things.
I would argue that Github is one of the best places for some information, like the exact chips used or maybe even very precise specs. There is such a thing as information overload for many people. As Framework’s sales expand, more and more regular consumers are buying. We are seeing this happen. People with much less technical knowledge are showing up with questions or just asking if Framework would be good for them as a basic user who’s not tech-savvy. Even very detailed specs, that are useful to you and me, can cause overload for basic users.
Those that truly need very precise specs, that most do not, should be accustomed to doing some research. So they should be able to find much of what they need. I’ll admit, it would be good if Framework could work toward having more available in a single place. Tho, the one time that I pointed out some information on this forum was not present on their Github, Nrp himself responded and had it fixed in a couple of days. And I didn’t raise the issue in the best, most appropriate place. Which would have been on their github. Framework does more than almost any other company I can think of. And we should remember, they are currently still a small, fairly new company. So I feel like, at this point in time, we can do a little research if we really need some minute detail.
But for the 3.5mm Audio expansion card I do think they should note on the item page that it’s a standard jack as found on the majority of laptops, maybe with a link leading to details.
That’s interesting can you post a copy of where Framework said that.
Yeh I agree. I definitely haven’t meant to imply the product listing needs details about which chipset is used etc.
Just the basic specifications for an audio output and input expansion card, which is: whether the 3.5mm output and input jack is stereo and mono respectively. It’s information that can only be helpful to a potential customer.
The rest of the marketplace product descriptions seem absolutely fine. The storage expansion cards include read and write speeds, the USB-C includes power specs and the HDMI card includes the supported resolution and refresh rate.
@amoun I am not sure whether I kept a copy of that correspondence, since I clean up my Email on a regular basis. But I will have a look in my “old” laptop. Maybe I archivated there something.
@amoun I found that correspondence. It reads as follows:
Re: Submission from Service Request Form: Audio-in
Betreff:
Re: Submission from Service Request Form: Audio-in
Von:
Lex support@frame.work
Datum:
16.11.22, 00:56
An:
privat@nvoelker.de
Re: Submission from Service Request Form: Audio-in
Framework Support
Hi Norbert,
Thanks for your reply. The 4-pole, 3.5 mm supports the Stereo-Audio in. The Framework Laptop comes with Audio Board that contains a 3.5mm headphone jack supporting four-button headsets.
Hope this helps.
Please don’t hesitate to contact us if you have any other questions or concerns.
Thanks for contacting Framework Support, and have a great day!
Regards,
Framework Support
On Tue, Nov 15, 2022 at 6:19 AM privat@nvoelker.de wrote:
Hi,
thank you for your quick response.
A follow-up question. 4pole usually means stereo out and mono in, just for headset use. I need a stereo in. Can this be configured as well?
Best regards
Norbert
Am 15. November 2022 02:00:50 MEZ schrieb Zeke support@frame.work:
On Tue, Nov 15, 2022 at 1:00 AM support@frame.work wrote:
Hi Norbert,
Thank you for your interest. Yes, the 4 pole 3.5mm jack in the Framework laptop can be configured to be used as a line in port. If you need further assistance, please feel free to reach out.
Thank you for contacting Framework Support. Have a great day!
On Thu, Nov 10, 2022 at 6:49 PM support@frame.work wrote:
Hi ,
Thanks for reaching out. A member of the Framework Support team will be with you as soon as possible. Responses outside of weekdays and working hours in the US may be delayed. If there are any photos, videos, or screenshots that would help us resolve the issue, please reply with them attached.
All Framework Support escalation staff will be out of the office on Friday, November 11th, in observance of the Veteran’s Day holiday in the United States. Escalation support responses will resume on Monday, November 14th.
In the meantime, check out the Knowledge Base, Framework Community, and our step-by-step guides for information.
On Thu, Nov 10, 2022 at 6:49 PM privat@nvoelker.de wrote:
Supportfrage-Kategorie: general-product-or-ordering-question
E-Mail: privat@nvoelker.de
Thema: Audio-in
Beschreibung: I am thinking of buying a framebook. One thing I want to use it for ist digitizing vinyl records. This requires an analog audio input. Is there any?
Best regards
Norbert Völker
Need additional help? Check out the Framework Support pages.
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Wow that seems to be a clear error, given other ‘comments’
I can see why you thought the ‘new’ expansion card may help.
I suppose you can ask for a refund at least on the ‘new’ expansion card given the wrong, confuisng info you were first provided.
That didn’t answer either, we know that line in works but mono ???
Definitely seems Framework did not deal with the support request at all well 
