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Hi: I've been lurking on this list for a while. You sure have a nice collection of experts here. Regarding the listmember with the noisy/hashy computer soundcard, I can offer a few thoughts from personal experience in my own studio. 1. most unbalanced computer soundcards seem to have grounding issues where they don't interface well with other gear, producing noise or hash or even hum. I think it's either lousy ground plane on the card, lousy grounding in the computer or strange ground issues being created by the computer's switching power supply. Even though it is a veritable interference/radiation factory inside a computer box, there's no reason why a quiet sound card cannot be built. Indeed, my old trusty Ensoniq unbalanced cards run very quiet and do not create hash/noise problems when interfaced with other gear. My card of choice on my DAW is a CardDeluxe, which is balanced +4dB pro-grade audio and runs dead silent. So I must disagree with the theory that an internal card _can't_ do pro-grade silent performance. I think many card makers don't build the consumer cards to that level of grounding and isolation. 2. a good example of a problematic card is the Soundblaster Live Digital card I use in my video-editing computer. It runs pretty quiet in and of itself but has issues when its shield is tied to the shield of most balanced gear in the studio. I'm guessing that's because the Dell computer's ground/shield plane that this card is using is not really greenwire ground and/or it's polluted or susceptible to pollution from within the machine. My solution, which works perfectly, is to bring the Soundblaster's outputs to tip and ring of balanced TRS connectors and leave the shield unconnected on the receiving end (opposite MO for sending signal to the Soundblaster). Problem solved. The card runs very quietly and actually produces credibly decent audio, particularly for video transfers of VHS and U-Matic tapes (which have lousy sound for the most part anyway). BTW, the digital part of the card has no issues. SPDIF in and out work fine with everything SPDIF in my studio (CD players, DAT machine, audio DAW, DVD player, etc). Thinking about this now, perhaps the soundblaster's DSP chip is the source of issues. I think SPDIF stuff may not move thru any or most of the DSP chip. 3. In the case of the gentleman who posed the question to this list, as I understand it he has unbalanced external equipment and unbalanced connections on the soundcard. I would suggest his best solution is a Jensen IsoMax box or an upgrade to a better card. I will again put in a plug for the CardDeluxe from Digital Audio Labs. I've used mine for hundreds of transfers and it's never let me down. Never lets me down for playback either; I route most digital sources in the studio through its SPDIF connection and use it for D-A because it's so honest. DAL sells an add-on AES and optical digital input daughterboard for it. Plus you can sync up to 4 cards (8 channels) for multi-track. End of plug. 4. The situation I described above with the Soundblaster card was also true with my old Dell 4100 box I used to use for video, so it seems to be a standard problem with that card, either all of them or my specific unit. As I said, no problems with an older/cheaper Ensoniq card in my workshop computer, which is a homebrew amalgam of castoff parts and is probably very noisy and hashy inside since it's in tight quarters and has two extra cooling fans, a separate IDE card, 4 hard drives and a CD burner. That Ensoniq problem has no issues going unbalanced out to the unbalanced in of my preamp in the workshop. Since the speakers for that system are right over my workbench, I hear hum and hash loud and clear if there is any. So, again, I'd say it's bad manufacturing practice on the part of some or many card makers that lead to this assertion that quiet audio _can't_ come from an internal card. -- Tom Fine