Windows – Acer Aspire V5 wifi connection drops & proximity issue

I am having a weird problem on Windows 10 with my wireless adapter recently. My wifi connections perform very poorly when my laptop is not in line-of-sight with the router. As soon as there is something between my laptop and the router, like when I move to a different room, the throughput starts dropping significantly to a point where my browser gets stuck and the wifi connection gets dropped and I cannot connect to it again until I am back in the same room as the router.

1. This has started happening since I performed a clean install of Windows 10.
2. This happens only on 2.4 GHz networks. 5 GHz networks work flawlessly.
3. I have Ubuntu installed natively as a second OS & I don't see this problem there. So i guess my hardware is not at fault here.
4. I never had such an issue with Windows 7, 8, 8.1 previously.
5. wifi signal strength is not an issue.

I have tried:

1. different driver versions.
2. different wifi networks on different routers in different locations with different levels of interference.
3. changing every available router setting value.
4. changing every available adapter settings properties.
5. Google, Windows 10 Feedback app, Microsoft help.
6. everything else i could think of.

System Info:
Acer Aspire V5-573PG-9610
Windows 10 Pro with latest updates
Qualcomm Atheros AR5BWB222 wireless adapter

I have been trying to tackle this issue for over a couple of months now. Has anybody encountered such an issue? Can anybody suggest anything that I might have missed?
Thanks.

Update: A full PC reset also failed to solve the issue