Sorry to hear that your speeds have taken a dip, are you testing your wireless or hard-wired speeds? Ideally we would like to see results from a hard-wired connection, if you don't have an Ethernet cable let me know and I'll get one out to you. Also, do you notice if your speeds change at certain times of the day / night?
Please get back to us so we can investigate further.
Take care and have a great weekend.
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