Bluetooth Mouse lag

Ok, this is getting ridiculous. The thread is half a year old, with dozens of people reporting the same problem, and there hasn't been any coherent reply from Microsoft whatsoever. My bet is they don't think the issue is important, so they just don't care. Alternatively, these forums are useless. I broke my mouse months ago, actually, but I'm just pissed that the problem hasn't been addressed yet.

I just spent the last few hours testing every possible combination of wifi (2.4 and 5 ghz), bluetooth, etc to see what is causing this, and it is not necessarily the Surface Pro.  One thing I had noticed is that I never experienced the bluetooth delay when connected to WIFI at airports, hotels, friend's homes, etc.  It was literally only happening at my home, so maybe the issue was somewhere else.  As most people know, bluetooth operates over 2.4 ghz which is the same as 2.4 ghz WIFI.  That is obviously opening the door to potential interference.

My home network is set up with wireless N on 2.4 ghz and 5 ghz from the same router (Linksys e4200v2).  Both wireless networks use the same SSID (part of the problem as you'll see later).  The bluetooth mouse would be stuttering and delayed every time I was uploading or downloading over WIFI regardless of my distance from the router.  It was also happening when using a USB ethernet adapter which thoroughly confused me as well and made me think it was not due to radio interference....but I was wrong there as well as you'll see below.

Since I have two Surface Pros on my desk right now (an SP1 and SP2), I decided to try various combinations.  The key to figuring this out was turning off wifi on my SP1 while leaving the bluetooth mouse still connected in order to isolate where the interference was coming from.  After doing that, I started a WIFI transfer on my SP2.  The bluetooth mouse on my SP1 began stuttering and was severely delayed until the transfer ended on the SP2.  That probably meant the WIFI signal was causing the interference and not anything hardware or software related within that specific computer (aka: outside interference can cause it too, which explains why all other computer manufacturers have similar complaints online...even Apple).

After that I did a data transfer via my USB ethernet adapter on my SP2 with its WIFI turned on to/from my NAS.  Again, the SP1 experienced bluetooth mouse delays.  That does not make sense as the WIFI was not even being used (verified as the data transfer was averaging 102 MB/s which far exceeds what WIFI is capable of), so what could be causing interference on the bluetooth radio at that time when the wireless connection should not have had data being sent or received?

Next I disabled just the 2.4 ghz wireless on my router while leaving the 5 ghz wireless on.  I tried a data transfer on the SP2 over ethernet.  No bluetooth interference.  Then I unplugged the ethernet adapter and did another data transfer over WIFI.  Again no bluetooth interference.  So the 2.4 ghz radio on my router was the culprit and somehow caused interference regardless of whether the data transfer was over WIFI or ethernet.

I then re-enabled the 2.4 ghz wireless on the router, and all of the interference issues came roaring back.  When I realized that I had both the 2.4 ghz and 5 ghz wireless networks using the same SSID, I checked to see which one the Surface Pros were defaulting to, and was surprised to see both were automatically connecting to the 2.4 ghz network when I had it enabled and only to the 5 ghz network when it was disabled.  So, I renamed the 2.4 ghz network with a different SSID which forced the Surface Pros to connect to 5 ghz only.

Time for more tests.  First I ran the data transfer test over 5 ghz with the router's 2.4 ghz turned on, but with nothing connected via that frequency.  The bluetooth issue persisted.  Then I disabled the router's 2.4 ghz wireless and ran the data transfer tests again over 5 ghz WIFI and the USB ethernet adapter, and there was no bluetooth interference.  Hoorah!!!!!

So, at least on my end, the entire issue was being caused by the 2.4 ghz radio on my router which triggered interference each time large amounts of data were sent through the router regardless of whether it was over wireless or wired.

Got a response from the German Microsoft Support again.

They told me they´ve got an answer for my problems from their colleagues in the USA.

The answer is: There is no solution for this problem yet. They are still collecting user reports and looking into the problem.

...

Well, I´m not counting this as an answer to my problem. It´s just an information to wait even longer.

Also, there is still no fix for another problem introduced with 8.1:

The Surface sometimes looses the information about the WLAN- and BLuetooth-adapter. Inside the device manager it looks like both doesnt even exist inside the device. Only a restart is helping.

If I go by Microsofts current performance with Surface fixes this new problem will only take 3/4 year to get fixed. If ever.

I´m thankful for Microsofts Support rying to help me but I´ve had enough of this.

I´ll try to return the Surface and get a normal Laptop (with Touch) again.

According to the Microsoft Supporter I can try to return the device but it´s not guaranteed to be accepted.

If it´s not working I´ll use the Surface as an extreme expensive remote for my home entertainment system as I won´t need Bluetooth for that.

A frustrated good bye.

I did some testing using my AP which supports both 802.11a/n on 5ghz/2.4Ghz

Using my SP1 and an MS Wedge Mouse, the stuttering/lagging problem only appears when connected to the AP using 802.11n on 2.4Ghz and only when uploading (used a large set of video files for testing to allow the connection to stabilize and allow a good stream not interrupted by "many small files" transfer logic) . The transfers were performed using SMB2 (SP1 using 8.1 with all updates to another Win 8.1 desktop machine).

Please fix it MS!

I did some testing using my AP which supports both 802.11a/n on 5ghz/2.4Ghz

Using my SP1 and an MS Wedge Mouse, the stuttering/lagging problem only appears when connected to the AP using 802.11n on 2.4Ghz and only when uploading (used a large set of video files for testing to allow the connection to stabilize and allow a good stream not interrupted by "many small files" transfer logic) . The transfers were performed using SMB2 (SP1 using 8.1 with all updates to another Win 8.1 desktop machine).

Please fix it MS!

This is not something that is fixable.  The same issue occurs on smartphones, iPads, etc.  I can duplicate it on an iPad 3, HTC One, Samsung 700 slate, and MacBook Air.  It is simply an incompatibility between 2.4ghz wireless N and bluetooth.