Ah. The deep bass is constant, the spike is mainly in the highs apparently - but also in mid-bass. I don't have a good speaker here now (I'm not in my office) so I'm purely speaking based on looking at the waveform in Audition. Will listen tomorrow morning.
-> Ok, re-read your comment and it wasn't about the bass at all
. Ok will check this one - it should go down way faster than it does here.
-> It's AGC Sudden Jump Protection. If I set the detection values to 5 and 8 instead of 10 and 16, the effect is mostly gone. I still have to test for side-effects (so far it looks good).
Edit: There are some side effects, but they actually appear to be good instead of bad. The huge spikes are removed before entering the multibands, so they move down less deep. And the initial spikes are caught by the AGC. So, I'll update this in the preset.
The effect isn't completely gone, but that's not really possible without killing all dynamics in dynamic tracks.