Updated...
Hi Rob, do not roll your SP4 back to a previous version. Your SP4 came with a new driver technology called WDI for WIndows 10. Never roll SP4 or Surface book back to a non-wdi driver.
We run tests in house with your exact setup "Comcast device" and are confirming now. For most people the following workaround will work. We do not have any known issues with this device.
For the regkey, here are the instructions
1.Press Windows button. Search for regedit. Open it
- Navigate to the following path:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\mrvlpcie8897
- Find the item labeled “TXAMSDU”. Double tap and modify the value from 1 to 0
- Restart the machine
Cause:
We have a known issue with .41 that results in low throughput with specific access points. The issue is specific to MAC layer aggregation (AMSDU over AMPDU) and only impacts a small subset of access points. We are working on a fix for an upcoming update.
Until the fix is available, please update the registry key setting to work around this issue
-Joe