We are experiencing exactly the same problem and our upload speed is significantly less than it used to be. This has occurred of the last 3 or 4 days. We are using a BT Smart Hub 6. Have run the BT diagnostic tool which reports we do not have a problem but we clearly do though intermittent which is why it might not be being picked up. Any suggestions
I moved your post to start your own thread as your problem maybe appears similar to the thread on which you posted but cause may be totally different this way replies will be specific to you
welcome to the BT community forum where customers help customers and only BT employees are the forum mods
in order for the forum members to help please can you post the stats from your router (if hub enter 192.168.1.254 in your browser) if HH6/SH2 then advanced settings then technical log information .
Have you tried the quiet line test? - dial 17070 option 2 - should hear nothing - best done with a corded phone. if cordless phone you may hear a 'dull hum' which is normal
enter your phone number and post results remember to delete number https://www.broadbandchecker.btwholesale.com/#/ADSL
have you turned of smart setup
have you split the networks
Someone may then be able to offer help/assistance/suggestions to your problem