Hi, I tried doing a search but couldn't find a similar thread. I recently purchased a pair of custom IEM tips and went through the process of having ear impressions done etc. The sound quality with the custom tips is really good, but I was surprised that the isolation wasn't better. At first I thought maybe my impressions had been taken incorrectly, or I wasn't inserting the tips properly. The company I purchased them from were very helpful and sent one of their agents to my work to check , but he said I was inserting the tips properly and there was no sound leaking out. I'm probably being stupid, but I thought the isolation would be a lot better with custom tips. However, I get much better isolation using triple flange tips or Comply foam / Shure olives. Can anyone who has had custom IEMs or tips done tell me if this is normal?