Different volume level for headphone and speaker

@alaug  just saw in the row of tags that you included "XPS 15 75900".  I assume that was supposed to be 7590.  In that case, according to the drivers page for that system on support.dell.com, it uses the Waves MaxxAudio Pro application.  I have that application on my own Latitude 7480, so if it looks the same on your system, open the MaxxAudioPro app, click the large Speaker icon in the upper-left corner to bring up the Playback interface.  Along the bottom edge in the center of the interface you should see an Advanced item.  Click that and make sure "Show pop-up dialog when device is connected" is checked.  From that point, when you connect a device to the 3.5mm jack, you should see a dialog asking you what you plugged in, and when you select the correct item, the drivers will load a present for that selection, including your last used volume level.  You can also use this preset functionality to do things like have EQ active only when using the built-in speakers and disabled when using external speakers.  I've found that EQ makes my built-in speakers sound much better and louder than they do when it's disabled, but it makes my external speakers sound muddled.

@alaug  independent volume controls requires Windows to be aware that there are two different devices in use.  In order for that to work when using a 3.5mm jack vs. the built-in speakers, the system's audio drivers need to actually treat the 3.5mm output as a separate device.  Some systems have audio chipsets with drivers that do that, and others don't.  You didn't specify what model system you're using -- fyi that information at a bare minimum is always good to provide when asking technical questions like this.  On systems that treat the 3.5mm output as a separate device, you'll either see separate devices listed under Control Panel > Sound > Playback, or else you'll see a popup dialog when you plug something into the audio jack asking what you plugged in, and if you select something there, the drivers will often change the Windows volume level to the last level used by that specific device even if Windows itself still only shows a single "Speakers / Headphones" device for the audio chipset.  But again, all of that depends on chipset and driver support.

If you're not seeing any popup prompt when you connect a device or any way to manage this, then your system might not support this capability.  In that case, the only option would be to use USB headphones instead, or a 3.5mm to USB adapter.  USB devices are ALWAYS treated as independent devices because they don't rely on the audio chipset at all.  They're essentially the equivalent of having a second audio chipset in your system.  The thing you have to be aware of in that case is that you want audio to switch to your USB headphones when you have them connected, go to Control Panel > Sound > Playback and set your headphones as the default playback device while they're plugged in.  When they're not plugged in, Windows will automatically fall back to your system's internal chipset, and when you plug them in again, it will switch back to the USB headphones.  You can do the same default setting on the Recording tab if you have a USB headset, i.e. one with a built-in mic, and you want to use that mic when your headset is plugged in.

Thank you @jphughan .

I followed your instructions and can see that "Load Preset" changes when I plug/unplug the headset. 

I can also confirm that the EQ profile settings are saved for each profile, e.g. when I increase one column for the headset then save and unplug the headset, the setting for the column changes back to the default value and when I connect the headset again, the previously saved value will be loaded. 

However, my main problem still exists. Volume level (the volume bar at the bottom of MaxxAudioPro) is not attached to a profile and cannot be saved for each profile individually. Am I missing another setting?

@alaug  if you're seeing the preset change without the volume level changing, I don't think you're missing any other setting.  My recollection from the systems I've worked with has been that volume levels are per-preset, but I may be incorrect about that, or that particular system may work differently -- and if it's the latter, I suppose in theory there might be a different setting for independent volume controls.  But my guess is that if it's not working at this point even with the preset changing in recognition of the fact that the output device in use has changed, then it probably isn't possible on your system. Sorry.

Thank you @jphughan .

I hope Dell Support has some thing to add.

I used to have this option in an older Dell laptop (don't remember the model,  but i got it early 2016). It's sad to see a useful functionality disappearing!

@alaug  I do too, although as I alluded to above, another option would be to either use a USB headphone/headset setup, or else get a USB adapter for your existing 3.5mm headphones/headset.  Here is one such adapter from a vendor with a reputation for quality products.  That particular adapter is workable if you're using conventional headphones or a headset that has separate headphone and mic jacks.  If you have a headset that uses a single "combo" jack, you'd need a different style of adapter.

Just a quick note XPS 13 7390 2-in-1 has exactly the same problem. It identifies headset but can't adjust volume.

This is simple to fix, and I have universal solution, regardless of your laptop. This was tested on lenovo b51-30 and Realtek, but I am sure it works with any model. Just remove your sound driver in device manager, commonly labeled as High Definition or something similar. Then restart PC. Then you will notice in driver details now driver provider is Microsoft, and not Realtek or any other company. That is the solution. You will still see only one device in Sound - Playback tab, but this is OK. Now to test, set volume when headphone are not plugged in to 25, then plug headphones, set volume to 50, now unplug/plug in, again, again, again...you will notice separate volumes being used depending on are headphones plugged in or not. Tested on Windows 10 20H2 in year 2021. See reddit post for more info including info if you need to disable automatic driver updates via windows update, so it does not change to Realtek or other driver provider again: https://redd.it/lj10u9

Of course this will now allow you to prevent accidental sound release if headphones accidentally unplug. Just set volume without headphones to 0 or mute. Other solutions like Realtek app advanced settings, Ellp app profiles, and github user's PrateekKumarSingh's powershell script PSAutoMute.ps1 did not work for me.