Difference in sound between copper and silver digital cables?

"For digital, it is primarily about no bit errors (which are highly unlikely) and no added jitter" That is 100% correct. When digital transmission improves (usb, spdif, aes) the sound signature will not "color" like an analog silver cable can do. Instead you get more low level detail, focus, bandwidth and precision. Its just more correct timed information for your dac to work with. Silver behaves better at the high frequencies (mhz/ghz) bands because the enhanced conductivity and bandwidth of silver itself at high frequencies. The skin effect is where most of the digital transmission happens. A good implemented copper digital cable can outperform a bad implemented silver digital cable. The implementation (geometry, shielding, dielectric, impedance matched connectors) is key. If these are exactly the same: silver will perform better.

If you have a high quality pure silver cable with impedance matched connectors it is about as good as it gets. For example Neotech nevd-2001,  Oyaide FTVS-510.  Just my 2 cents

I compared silver AudioQuest Truth interconnects to copper AudioQuest Truth interconnects both 1 meter air dielectric and copper sounded better. So that is one case that disproves the general theory. 

Just some anecdotal evidence doesn’t disprove general theory. I cannot find Audioquest Truth Digital interconnects in copper or silver version for digital (spdif/aes/usb). Is this an old cable? If it works for you. Well, go for it. Audioquest is very good but overpriced. And I know. I have seen their manufacturing and assembling of cables first hand.

while I agree with tantejuut in principle, practically, in audio, the lack of proper impedance control (RCA or XLR), and the limited bandwidth of the connected digital circuits is going to make any bandwidth issues between copper and silver inconsequential, i.e. the circuits can't take advantage of any potential bandwidth improvements of the silver (that could be replicated with a different copper construction in most cases). Due to that skin effect, there is virtually no benefit to pure silver, as plated silver would provide all the high frequency benefits.

heaudio123 that is correct