Geoffkait, yes that is interesting. I *think* I reversed the glass one--it's something I'd be likely to do--but I can't recall for certain. Once the ceramic went in, I was happy again and thought no more about it.
Fuses that matter.
I have tried six different fuses, including some that were claimed to not be directional. I have long used the IsoClean fuses as the best I have heard. No longer! I just got two 10 amp slow-blows WiFi Tuning Supreme fuses that really cost too much but do make a major difference in my sound. I still don't understand how a fuse or its direction can alter sound reproduction for the better, but they do and the Supreme is indeed! I hear more detail in the recordings giving me a more holographic image. I also hear more of the top and bottom ends. If only you could buy them for a couple of bucks each.