Make sure the soundcard volume is on max, rather than the amp.
pdq is right. Best practice is to use the last volume control in the chain to set your level with all preceding controls set to the highest level that does not cause clipping.I want to see Rightrark analyses for all devices in question in order to show their noise floor any anything else that might suggest that they could sound different. You don't get to say something has hiss or "think" something sounds better than the other without objective evidence. If you can't provide the evidence don't make the claim."i get Hiss, and it must come from the Soundcard" is a claim that needs substantiation."i do think the Motherboard beats the other" is a claim that needs substantiation.Please don't waste other people's time. A lack of compliance will lead to thread closure.