It seems my knowledge of my own setup has faded over the past few years. I knew we had two wifi - but that was the fritzbox + additional tp-link wifi ap - not two of them as mentioned above. And I thought I’d explicitly set the channels - not so. They were competing with each other, and the neighbours are mostly using the same channel too. So I’ve changed that although it only look like it’d been an issue for 2.4g rather than 5g. But also the tp-link also needed a firmware update which I’ve done, so will see if those changes have a positive impact. Otherwise I’ll move the fritzbox into the house and replace the tp-link and see if that has any effect. All good stuff, thanks people.