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We have a mobile wifi router (Vodafone Mobile WiFi R219h) which has recently not been working as well as it used to. Lots of buffering on tv etc....
We pay monthly for unlimited data and the router was part of the package when we signed up. Can we get a replacement from Vodafone for free or would it be better to see if we can get another one unlocked? If that is possible? If it is then are there better ones out there that would cope with three teenagers, an old house with thick walls etc....
There are a few different ones to choose from and each has their own merits.
A Google search and forum search may help.
A Vodafone Highstreet Store can look at it for you and it may also be beneficial to check your masts , both local and surrounding to see if their are any issues.
Sometimes re booting and turning it Off and On can help too @Pudpeachey
Current Phone >
Samsung Z Fold³ 5G.
Previous Phone >
Samsung Note 20 Ultra 5G - SM9860.
Television streaming is best done from a fixed broadband connection, if you are going to be depending on a mobile signal, you are going to expect some buffering and drop outs.
The speed you will be able to achieve will also be dependent on the number of devices connected at the same time, you also mention that you are in a property with thick walls and have three teenagers connected using the internet.
As you are using an R219 you should be receiving the fastest speed possible from the network. If you are unable to get fixed broadband, the other alternative is the Gigacube here: Gigacube but that is still dependent on a mobile signal. Take a look at mobile repeaters, but this is going to work out expensive. Further help from Ofcom here: Mobile Phone Repeaters