I have the same problem. Switched over from Sky to Now TV, going from the Sky Unlimited and upgrading to Now TV fibre with the aim that i could put some of the savings into better fibre broadband. What a mistake, Now TV broadband has been shocking, slower than Sky and it keeps on going completely or being very slow. They sent me a new router and no change.
Called them last night and their excuse was that it was because i had 20 devices connected to the internet. Well considering 4 of these are access points, 5 are Sonos which uses barely any data when not being used, 2 Echo Spots, 2 phones, a PS3 and PS4 (both in standby) and a couple of watches, an ipad and the NowTV Smart Box. The girl i spoke to obviously has no clue about networking and said that the 50MB i should be get was split between 20 devices!!! So her argument was that Netflix was cutting out because my dormant sonos speaker was using 2.5MB!! Shocking service. To be fair they answered the phone quickly, but then i was cut off twice without warning, and then then i called back she couldn't stop laughing, presumably because the guy next to her was the one i had just spoken to and was making hand gestures or some such.
Its not good when the support staff doesn't even know what an access point does, doesn't know what Sonos is and has no understanding of what she is supposed to be advising me on. Her solution, to turn off lots of devices that are accessing the internet and to change my wifi channel to channel 6, a solution that i can't see will affect my Smart TV and laptop which are both connected by LAN cables.
Laughable!! Have done all they suggested and will wait to see if it resolves it, then hopefully cancel and find a better solution.
Im having the same problem. Im supposed to be getting an average of 63mb/s but ill get about as high as 40mb and as low as 1-10mb. I just recently got it installed and had to get an engineer visit because it was linked to the wrong house.
I have never had such terrible internet since moving from Sky to Now TV broadband. Literally counting down til our 12 month contract is up as we can now barely use a single device without it freezing and losing connection. Currently got my laptop on a phone hotspot as I can't get on my broadband despite being sat in same room as router. DO NOT MOVE TO NOWTV BROADBAND!!
Have you still got your old Sky Router ?
If so, have you tried the Sky Router in your home setup instead of the NowTV Router, just in case you have a defective router that is encountering wifi problems ?
I know every case is different, but my NowTV Fab Fibre has been stable and excellent since i joined in April, where i haven't noticed any difference in performance moving from BT (apart from more money in my pocket).