errm its pretty likely from the picture that they are decoupling inputs and acting as local reservoirs for the supply lines of the receiver and dac chip. the application calls for a lowZ, low leakage cap, oscons are pretty much unmatched for the position they are used here (only thing better would be the SEPC version or otherwise SMD type package of same). they have about the best spec for lowZ at HF (for electrolytics) going apart from NPO ceramic and some films, which the PCB seems to even have placement for too. those through-hole thin rectangular positions on the component layout there seem to be there for adding wima/evox/vishay MKP or similar to bypass the sanyos, that would be what I would do anyway and it seems they have made it easy for you.
I see mods all the time on here and around the net, basically removing suitable caps, only to replace them with ill-suited, ill-fitting inductive nightmares, replacing very low capacity (20pf or whatever) SMD NPO ceramics decoupling very HF signals with a comparatively slow and ineffective 100uf BG, without regard for (and most often knowledge of) what the caps are they are replacing; simply because they are SMD or not a brand that is as 'audiophile approved' as blackgate. hell sometimes its done with a complete DIS-regard for what is called for in the datasheet
