Tonight I started looking at ITMX modes that are close in frequency.  Mode 7 is at 502.784, and mode 8 is at 502.909.  I checked the damping filters, and mode 8 damping filter was biased toward the mode 7 peak, so I shifted that bias to be away from the mode 7 peak, saved and loaded the filter file.  On can see where I loaded the new filter because the drive on mode 8 starts to grow, and the LOG10 signal increases.  I turned the gain to zero, and waited, and then tried a smaller positive gain, and watching dtt, I could see that again mode 8 was ringing up, so I tried a negative gain, and at the time of the snapshot mode 8 gain was -20, and the mode was damping/damped quite nicely.  Mode 7 gain remains at it's nominal of +10.   Now that mode 8 is damped, I'm turning down the gain, and will alog that number at the end of my shift.  Mode 7 and mode 8 damping filter bode plots, and the time series showing the -20 gain on mode 8 are attached below.