That is the same as my setup. I think the only way I can change this behaviour is my audio driver provided software that has an option for Independent Front Headphones, you could check if your new drivers have installed any application that may have this option.
I've looked at 2 other different images of this dialog and yours is different again. I honestly don't think you will find a solution. You can try Google as I have had a quick search and found a couple of pages with the same problem neither had a solution.
You could try another version of the driver, Fujitsu has a Vista driver, a much earlier version that might have this option but it may not work with Win7 and theres the chance the ALC260 doesn't support this feature. You'll find that driver here Technical Support pages from Fujitsu, just put your serial in the box provided, click continue, select Win Vista and Win Vista again, select Audio and click download on the right.
Otherwise you could live with it and like me (even though I have that option) turn off the speakers or unplug the headphones depending on which one you are using.
Let me know how you go but I have to go now I'll check back tomorrow.
The Vista drivers should work OK for Win 7. We tell users on the Dell forum that have upgraded to Win 7 and there are no Win 7 drivers, but there are Dell Vista drivers, to use the Vista drivers and they work OK.
My Computer
At a glance
Windows 10 64 bitIntel i7 6700K16GB Corsair DominatorIntel CPU Graphics
Computer type
PC/Desktop
Computer Manufacturer/Model Number
My Own Build
OS
Windows 10 64 bit
CPU
Intel i7 6700K
Motherboard
ASUS ROG Maximus VIII Hero
Memory
16GB Corsair Dominator
Graphics Card(s)
Intel CPU Graphics
Sound Card
RealTek
Monitor(s) Displays
27" Dell S2719dgf
Screen Resolution
2560X1440
Hard Drives
1 TB Samsung 850 EVO SSD for Win 10 Pro
500GB Samsung 850 EVO SSD for Win 10 Insider
2 TB drive for backup
PSU
EVGA Supernova 750G2
Case
BeQuiet Silent Base 600
Cooling
Deepcool Captain 120EX
Keyboard
Microsoft Wireless 2000
Mouse
Microsoft wireless
Internet Speed
100 MB/sec (Cable)
Antivirus
Microsoft Defender and Malwarebytes
Browser
Edge/Firefox
Other Info
Cakewalk (Sonar) by BandLab and Studio One 4.1 Pro recording studio software. MOTU 896Mk3 Hybrid recording interface, Frontier Tranzport wireless control unit, Behringer X-Touch Control Surface.
Five USB connected optical drives for CD Audio production using Nero BurningROM
You could also e-mail Fujitsu and Realtek and ask them for any advice. Ask if independent front panel is supported by the ALC260 on Win7 or muting the rear, what driver versions support this and even send a link to page 3 of this topic.
Wish I could help more but I don't have a MB with Realtek audio to investigate futher. I can only suggest the e-mails, trying different driver versions and Google.
