Airplay and iOS9

New to RPi and stuff, so apologies if this is a shairport issue (suspect it is, but don’t know where to post for that).

I have two separate Pis in different rooms, both running MusicBox 0.6. I’ve been using them individually (one in the kitchen, one in the lounge) and together in sync using a combination of Tuneblade and shairport4w on a PC. It’s all been working great, until I stupidly upgraded to iOS9.

Now, if I use the multiroom via the PC (from iPad to shairport4w, then Tuneblade to the Pis), everything still works great. If I just want one room on though and stream directly to a Pi, I get dropouts approximately every 30 secs, for a second or two. It sounds awful. This worked perfectly with iOS8. Very frustrated!

Anyone else experiencing these issues?