Unable to load web pages when uploading data (YouTube or Dropbox etc)

Hi, as per the post linked below I am also having problems with my TalkTalk HG633 router.  When uploading data to YouTube or Dropbox, no device on the home network, wired or wireless, can load any web pages, not even a basic page like Google.

https://community.talktalk.co.uk/t5/Fibre-Broadband/Issues-with-Router-when-YouTube-uploading/td-p/2410590

It appears to be a common problem with the TalkTalk HG633 router.  Please advise on a replacement?

Thanks.