Thanks for answering. First of all, as I asked in my previous post, Is there a name for the modulation I described in the previous post ? I want to check more on the internet about the phenomena. I am sure, in my case (the amplified speakers at least, it doesn't manifest on receiver + passive speakers), it's too much and the speakers have a fault (defective at birth or a flaw in the design). I thought frequencies stay flat (or at least to inaudible levels) at all range, regardless of how rich the sound is (simple samples, frequencies or a lot of channels of all levels, mixed together). That is one problem. The second one is the distorting (the ssss-es became sshhhh-es - again, I don't know the term) and the third one it seems sound is losing a certain warmness, I mean it sounds kinda metallic. The last two problems I am sure are sound card related. I am aware I am making a big deal out of it and in the end I must replace the sound card, but all I wanted to know if that there is something wrong inside my computer that damages the cards and / or am I setting something wrong that also damages the cards. I am afraid a new sound card will manifest (more or less) the same symptoms after not so long and I don't want to waste money, on a limited budget. I am not a sound expert, I mean, not on a technical side, I do graduated a college somehow related, but haven't practiced on the field. But I like to believe I have a native good ear that recognizes what sound should be. I mean, I can spot anomalies of all kinds, even though I can't describe them technically. That's why I asked. Something is definitely wrong and don't know if inside the card or the amplified speakers. To protect the receiver, I stopped using it, to prevent potential damage, if something is wrong with the audio card output.
You said about cleaning the card. I am not contesting, but I don't know what exactly to clean. The contacts between the two cards (audio and motherboard) and from the card and front panel ? Or every electronic part (resistor, condenser, chip, etc.) ? This would be a titanic work. And I don't get it what dirt can do from the outside, other that parts accumulating heat. Even then, heat and humidity are within limits inside my computer. I had more cards inside computers I had since 1996 when I had my first PC and so far, cards worked fine, no dusting, cleaning or anything. But again, I won't dispute the theory, it's just I believe it works on higher levels, not a mere and regular computer user, where we don't talk about high precision.
About the last part, I don't get it. From the comments, it seems you believe I did something wrong, but I don't understand from your post, where. I am leaving Winamp EQ flat and preamp at 0 dB and only after that, I am boosting high and low frequencies from the sound card output. Active speakers don't have bass and treble knobs, so I must set the EQ from the sound card. Is this wrong ? What do you mean I might LOOPED anything ? What exactly is this ? You are using many technical terms I don't understand. I am not an expert and my equipment is not a professional one. It does have all sort of settings and it's not the cheapest, but although expensive in it's own range, it's still a common equipment, not a professional one, not designed to have that many tweaks and desiring a lot of engineering knowledge, to sound acceptably good. But, as it is now, it's far from good.
Can you please elaborate, when you have the time on the terms you described above, where do you believe I go wrong, if, by the symptoms I described, do you think it's something wrong with my card, phones or speakers and if so, how can I test it, using minimal equipment, preferably self testing software (that checks for anomalies) ?
Also, I am not using phones output to my active speakers. My active speakers are connected via digital coaxial cable on the sound card.
Again, many thanks and Happy New Year!
This post has been edited by Phaenius: 31 December 2012 - 01:05 AM