They are just the power pin bypass caps of the cd4052, so nothing critical. I don't know the value but most likely they are 10nF or 100nF or something between those values like bypass caps usually are. It should work pretty well without it as well, it's only an analog mux and most likely it is not switched very often.

Yeah, I figured that it is not super critical, I think it is used to switch between the outputs. I received this card as faulty (it was very cheap). There was virtually no output on any of the channels. Looking at the card I noticed that the -V input on the cd4052 was burned away. I replaced this chip and figured that the amp must be shot as well. Just now I replaced the amp chip. When I put the card back in and powered on, the trace running from the -V to the c95 burned away in a pretty flame. I also found that there is a trace running from -V on the underside of the card, and that was burning too. I think there was a short underneath the chip or something, so I cut the trace on the underside to stop the short. Interestingly the output now works, I can hear everything properly on Output 1. Output 2 crackles like crazy, it seems the fault is there (it is supposed to be the headphone output).