Are you using the "Best" Amiga Browser ...IBrowse. If so you may notice that after using it for a while, You start to find it takes longer and longer to load. This is a simple cure for the problem caused by cached downloads.
Open your download window & check the last 2 tabs. If downloads are cached, you'll get a slowdown over time. Remove all & see if it helps. You can turn off the download cacheing in prefs network by unchecking the "log downloads" box.