I mostly listen music from Spotify Premium HQ, from my laptop, using a Fiio E7 USB DAC. I'm definetely no audiophile... and my taste of music varies from hard rock to jazz or even lounge music wildly. I have a Sennheiser IE8 IEM which I bought more than 10 years ago (gasp) and use it as a daily driver since then. I always handled it with care, but this week it just started to malfunction - the right channel volume is about 40% lower now. I searched around and saw it a returning problem for this IEMs and it might get resolved with a new cable. However... About 2.5 years ago I bought another, cheaper set of Sennheisers, a Momentum IEM, for snowboarding. Since the day of this purchase, I was unsure about my IE8 - the Momentum felt much brighter, sounded clearer and the IE8 sounded a bit muddy in comparison.. but then again, the IE8 still felt to have a wider soundstage and much more details. (Ideally what I apppreciate most in earphones is a huge soundstage and clean, less-punchy bass with balanced mids and clear highs, though the Momentum IEM has somewhat painfully crisp highs, that's a bit too much I think). Now that my IE8 broke down this week, I wonder what I shall do next. Plans include: A) buying a replacement cable for my 10+ years old IE8 (cable is ~$30 herearound) B) use the Momentum as my daily driver from now C) look for an IE8 replacement - maybe an IE40 Pro? D) maybe try something completely different? But I have been pretty much satisfied with my Senns IEMs in the last 10+ years.. And to the actual questions: - How do IEMs age? Can it happen that my 10 years old IE8 sounds much more muddy than at the time of purchase? - Maybe technology has improved that much that I feel the Momentum better on several fields than my old IE8? 10 years is a long time for sure... - How would an IE40 Pro compare to either of these 2 IEMs? I have no wide experience with various brands and products so I could only use openions comparing to these two unfortunately. Thanks a lot for your openions and advices in advance..