Bluetooth Low Energy Lag / Latency on OS X 10.11 El Capitan

I am running OS X El Capitan 10.11.6. I have a brand new Ganglion that
just arrived last week, and have been using the Process GUI to gather
data. Everything seems to be working correctly.

We have made a
simple web-app to show images to a subject. This web-app records a start
and end timestamp (in milliseconds) as the image is shown and removed. The hope
was to match this to the timestamp in the Ganglion data log file.
However, the data file seems to have multiple readings for a given
timestamp (I have pasted a sample below). For this application, we may have graver problems than millisecond errors, but I am curious
if there is a solution for the timestamp discrepancies all the same.

After quite a bit of poking around, it seems like the answer might involve adjusting the "connection
parameters", the slave latency in particular, in the Ganglion analogous
to what is discussed for a different BLE device here:
http://stackoverflow.com/questions/35197335/bluetooth-low-energy-lag-latency-on-os-x-10-11-el-capitan

If doing such a thing would be at all relevant, how would one go about
altering the connection parameters from OS X? Could Bluetooth Explorer
be used? (I couldn't see anything relevant in that application for doing
this.) I looked in the Process GUI code for relevant parameters but was
not able to identify them. I noticed that in the openBCI python repo
https://github.com/OpenBCI/OpenBCI_Python it is possible to modify the
connection parameters of the Bluetooth adapter. Could such a thing be
done for the native OS X Bluetooth?

Thank you so much for your help!

---------------------------- Ganglion Data Log File ----------------------------
0, 1.10, -5.02, -0.44, 16.92, 0.000, 0.000, 0.000, 20:01:28.997
1, 6.05, 17.72, 3.16, 22.55, 0.000, 0.000, 0.000, 20:01:28.998
2, 12.51, 19.24, 19.08, -3.19, 0.000, 0.000, 0.000, 20:01:28.998
3, 2.85, 9.18, 10.36, 12.77, 0.000, 0.000, 0.000, 20:01:29.025
4, 7.65, 6.00, -1.10, 26.71, 0.000, 0.000, 0.000, 20:01:29.026
5, 10.11, 15.53, 13.78, 4.36, 0.000, 0.000, 0.000, 20:01:29.026
6, 4.81, 7.84, 8.38, 6.65, 0.000, 0.000, 0.000, 20:01:29.026
7, 2.59, 9.55, 2.50, 23.09, 0.000, 0.000, 0.000, 20:01:29.027
8, 8.65, 15.70, 11.91, 12.55, 0.000, 0.000, 0.000, 20:01:29.027
9, 8.23, 14.73, 14.16, -1.13, 0.000, 0.000, 0.000, 20:01:29.028
10, 0.91, 8.76, 7.62, 16.47, 0.000, 0.000, 0.000, 20:01:29.028
11, 3.68, 9.34, 8.44, 16.23, 0.000, 0.000, 0.000, 20:01:29.055
12, 10.28, 23.94, 16.47, -9.47, 0.000, 0.000, 0.000, 20:01:29.055
13, 3.93, 12.42, 1.19, 11.37, 0.000, 0.000, 0.000, 20:01:29.055
14, 4.49, 2.98, 1.18, 28.03, 0.000, 0.000, 0.000, 20:01:29.056
15, 4.09, 12.73, 18.33, 3.41, 0.000, 0.000, 0.000, 20:01:29.085
16, 7.92, 12.57, 7.93, 10.14, 0.000, 0.000, 0.000, 20:01:29.086
17, 2.60, -0.86, -2.95, 24.31, 0.000, 0.000, 0.000, 20:01:29.086
18, 6.84, 15.49, 10.48, 12.39, 0.000, 0.000, 0.000, 20:01:29.086
19, 10.35, 12.33, 10.05, -4.89, 0.000, 0.000, 0.000, 20:01:29.086
20, 2.93, 4.73, -1.97, 18.28, 0.000, 0.000, 0.000, 20:01:29.086
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