Hi, a friend of mine has done something stupid and created a feedback loop. He is now worried he may have damaged one of his components. His setup is as follows: Decks into mixer (analogue) mixer into amp (analogue) amp into computer line in (analogue) and also to Kef Eggs computer spdif out (digital) into amp Decks | Mixer | Amp--Kef Eggs || Computer This is so live mix sets can be recorded onto his pc. If his pc wasnt connecting back into the amp then this setup works fine (this is needed to listen to audio from his pc), but because it is its creating a feedback loop. As the signal from the pc is digital the amp prioritises this and overrides the analogue signal from the mixer. This caused major feedback and sound distortion. Could this have damaged the pc motherboard/ amp or speakers? He is concerned the sound is grainier than it used to be. If damage occurred could it be negligable like this or is it more likely to have been more obvious ie blown speaker or crackling noises (meaning he can relax as its probably just his imagination?!) Any advice is much appreciated.