I guess you have sensitive ear canals like me. I've had luck with Klipsch bi-flanges wrt maintaining deep insertion, but you give up some isolation. Another thing that helps is not wearing them for extended periods at first, work your way up. When you get irritation take a break for a day or two.
It's not really irritation. It's like when the IEM moves a bit, the suction pulls on my eardrum and it causes a lot of pain for the next day or so.
+1 on all of that. However, my ears are still sensitive sometimes. I can wear the er4s with large triflange as deep as the pictures I've shown for hours with no problems. Other times I swear I wear them like that for 30 minutes and my ear has a bad pain the entire next day. Perhaps the tip pushed against my canal just enough in one case and not the other? I don't know. I just know that they do have the unfortunate side effect of sometimes being very painful. It's too bad, because otherwise I think they're the best iem i've ever heard.
My solution is to use the small silicone tips from my pfe series. Those don'e cause any pain and seal even easier in general. However, they are more prone to popping out of the seal and losing the perfect response because of it. So with those I usually only wear them when I'm not moving at all (sitting at computer, lying in bed). Otherwise they just don't work.
Absolutely best isolation ever. Better than any earplug I've ever used too. Noticeably.
As for criticality of tracks, I never found this a problem like some people. I think if you don't have a perfect fit and therefore not a perfect bass response, the treble will then exaggerate any sibilance and flaws in that regard. However, with a perfect fit and especially with a bit of sub bass boost eq, I don't find this at all.
I'm still surprised. Maybe my seal and depth were great, but I had a poorly mastered 116kbps track that had new life breathed into it.
Foam tips usually don't work for me =(