I see Pete has already kindly linked to the FAQ on this, but just to reiterate, you don’t need audiophile network cables.
Until the network data hits the DAC or the endpoint, it is just network data, not signal; it behaves no differently to any other network data being sent via TCP. If there was any sort of improvement that could be made to the integrity of the data packets being sent over a network by introducing additional shielding to the cable or different material conductors or any of the additions such audiophile cables tend to include, it would have been picked up by the IEEE and incorporated into the Ethernet spec as, for example, it would save banks billions a year in random lost transactions.
Aside from this, audio (even hi-res audio) is so low-rate compared to what most residential networks can handle that there is no reason to need anything above CAT5e for speed purposes. Purchasing a CAT7 cable doesn’t help anything other than lightening your wallet when it comes to audio. To put it into context, both Andrew and I have access to almost any cables available on the market, and we both use cheap and cheerful Ethernet cables from Amazon.
Networks are one of the few places where keeping things as simple as possible is usually the best way to go. You are striving for a network which is stable and reliable, not one which sounds good. Much better to put that money into some really good AES cables, or perhaps a good bottle of wine or whiskey for the evening.