I initially had trouble streaming 24/48 FLACs in my small home. I have an old-ish house (1921) with a narrow, closed layout -- bunch of small rooms stacked inline, lots of thick walls. I started off not getting strong enough wifi reception from one end of the house (home office w/ music server and wifi access point) to the other (living room and listening space) for 24/48 files. 16/44 worked fine. I ended up installing a hacked firmware on my wifi access point and boosting the signal. 24/48 files played fine, then. Plenty of other solutions if you have signal problems: hardwire, wifi repeater/bridge, powerline network adapter, etc.
On a related note: not all Squeeze devices play 24/96 (most resample to 24/48 on the fly, I think), so confirm the specs of the unit you buy if that's a concern.