BT Cloud Windows App Massively Slowing Down Broadband

[Sparky86]

Just wanted to ask if anyone has noticed this behaviour from BT Cloud - with both download speeds and upload speeds massively slowing down when I am using the BT Cloud desktop app to upload files.

I have recently gotten to about 90% filled up on my PC's disk drives (2.5TB total across 2 SSDs and 1 HDD) and I also recently filled up the 1TB on my OneDrive, which is my preferred cloud product. I have an Office 365 subscription anyway (usually pay monthly for it, but recently just got 1 year free with a laptop which is nice) and I definitely prefer OneDrive's integration with Windows and its features/usability. However I wasn't keen to pay extra for more space when I have another 1TB from BT already included with my broadband package, and also can't afford to upgrade my SSD currently either.

So I thought I would use BT Cloud to backup my film and TV show library of things I have already watched - over 500GB of stuff, that I won't need fast access to so no point being on my PC's disk space but I'd like to keep somewhere just in case I may want to watch something again. So I thought BT Cloud would be ideal for that. It was annoying to find the 2GB file size limit on the web interface so I downloaded the desktop app and set it to back up my desired folders.

Just over a week ago I noticed my broadband speed and latency regularly becoming very bad, for example it can drop to below 1Mbps at some times, and have a ping of 400ms. Sometimes it will be OK for half an hour or so then drop down for either a short or long period of time. I couldn't understand what was going on and tried various things to fix it - checked cables, powered router (a Smart Hub 2) off and on, then reset router completely but I was still getting the same problem. When I tried the troubleshooter on my BT account it would determine my line speed was very slow and try fixing it, and the speed would be fine again for a short while then go really low again. Eventually I called BT and they tested my line which was apparently fine. They sent me a new router just in case - my Smart Hub 2 was an FTTP model even though I only have ADSL, as I was originally going to get FTTP a few years ago but they weren't able to install it in the end. BT weren't sure if that would make a difference but replaced the router just in case. I was still having the issue so they sent an engineer.

The engineer also couldn't understand why I was having this issue as my line was fine, he replaced the telephone socket panel and we also made sure the filter/router were plugged directly in rather than using the extension cable I usually had in place, as I would have my desktop plugged in with ethernet but the phone socket is on the other side of the room. So we still couldn't work out what was causing this issue - any other devices connected to the router by WiFi would also be getting very poor speeds. The engineer said to leave it a couple of days to see if the connection would improve, and to call BT again if it didn't.

Yesterday I believe I found the cause - the BT Cloud app! It crossed my mind just to monitor the broadband with BT Cloud paused and it was then absolutely fine until BT Cloud was resumed. It didn't cross my mind the cause could be BT Cloud before as I started using it about a month ago, but the broadband problems began about a week ago. Also, it is set to backup only, not sync from the cloud back to PC. I only have OneDrive set to do that, and that is only with small amounts of data - such as documents or photos created on my phone. So BT Cloud should only have been using upload capcacity, not download. 

I still don't understand what the hell BT Cloud can be doing to cause such connection issues. Every other device connected to the router also experiences download speeds that can be below 1Mbps when BT Cloud is uploading, and as soon as it's paused they go back up to normal. OneDrive doesn't cause any of these issues at all - download speed isn't affected when it is uploading. Even with this bizzarely significant effect on internet speed, BT Cloud is very slow at uploading files and there is also no way to limit its bandwith usage.

Does anyone have any idea what BT Cloud could have been doing to cause my issues?

[ckp1975]

We ran into the exact same issue and went through the same process as you.  I informed the BT customer service - they did say it was a known issue, but it appears their Qube engineers need to asking the specific question about cloud backup and in particular usage of the BT Cloud App.  Suffice to say we have stopped using the BT Cloud App and everything is fine.  Like you we have never had problems with Microsoft One Drive.

[pddco]

@Sparky86 If all you’re doing is backing up your files I’m not sure why BT Cloud should be impacting your download speed. I’ve had it installed on my PC for a few years now and not come across that issue. Clearly when uploading it will take as much as offered by your upload rate. It would only download stuff if you were trying to synchronise with other devices that had the BT Cloud App (Mobile or Tablet for example) Or another PC’s BT Cloud folder. Saying that, in any case it’ll take quite sometime to upload 500GB of files. On a 80/20Mbps package you’re only uploading at roughly 2MB/s. And with 500000 MB to upload - well that’s days rather than hours. May need to run it over several nights perhaps? Just a thought.

[pddco]

@Sparky86 @Apologies. Just re read your post. You’re not downloading stuff / syncing with BT Cloud folder as far as you know,  so it does seem rather strange that download is being hammered. One thing you may want to try, if you haven’t already done so already, is to check your broadband speed using the MyBT app. That’ll confirm speed to / from the hub directly  (rather than to a device connected to it). If you do this with BT Cloud paused and running you should be able to see what affect it’s having on the actual  Broadband  line speeds rather than including say any Ethernet or WiFi connection to a device. Hope that makes sense.