Network drives/shares constantly disconnecting (affecting Time Machine & Music syncing)

Since buying a new MBA (2024 M3, Sequoia 15.3.1) I've hd problems with two network shares constantly disconnecting, both while in use and when not. This was never a problem with my previous MBP, that spent most of its life on Mojave and Big Sur (which was its max macOS version). The two network shares are my NAS (connected by SMB) and my Time Capsule (connected by AFP). My NAS houses all my media, and I use Music (previously iTunes) to Airplay my library to an Airport Express connected to my amp and speakers. Worked perfectly for years, with the occasional drop out here and there as you come to expect from Airplay. But since moving to this MBA, I just get drops outs all the time - sometimes I can't even finish a son without it dropping out and Finder losing connection with the NAS

Sometimes it's a blip and it remounts itself, but most of the time I have to go remount it manually (I made a little AppleScript I can execute to remount it). This is causing problems with syncing music to my iPhone, as it will sit there for for ages on step 3 (determining what tracks to sync) and then 20 mins later report it couldn't complete the sync).

Likewise, I'm getting Time Machine backup failures because it loses connection with the Time Capsule drive.

I've read that others are having similar issues with NAS/network shares, so I'm hoping that's ruled out it being a problem with this MBA's wifi card. My network seems stable enough, and I'm not having this issue with my previous MBP on Big Sur, so I'm hoping this is only a software issue within Sequoia and it can be fixed. At one point when I set this MBA up, I had to mess around in it's settings as I couldn't even get connected to my network drives due to it's new privacy "features" prohibiting access.