Galean Kruger 200MB Problem

[snipeguy]

My wife ordered a new speaker for her 200MB. The surround on the old speaker disintegrated. I installed it tonight but it does some weird stuff now. When you hit a note, it seems like the signal is cancelled for a second. Kind of like it's out of phase or heavily compressed. the harder you play, the worse it is. At some points the signal dissappears completely and slowly returns as the note rings through. It's the attack that does it. Also the speaker moves in and out very slowly. A high note doesn't seem as bad. Is it something to do with the airtighness of the enclosure? It was really sealed and I had to break the seals to get at the speaker. This was a special speaker that we waited for three months to get and now this. Any ideas?