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Another question about gUSBamp configuration...

I am recording with two gUSBamps connected with a sync cable. I have noticed that, seemingly randomly from run to run, the slave amp is aligned with the master, leads it by one sample, or lags it by one sample. This is causing havoc on my data processing.

SourceCh: 22
SourceChDevices: 16 6
DeviceIDMaster: UA-2006.10.05 (this is where the sync cable is connected to SYNC OUT)
DeviceIDs: UA-2006.10.05 UA-2006.10.06

I tried using AlignChannels: 1, but this made no difference.
I am hesitant to use SourceChTimeOffset because the offset seems random each time.

I recorded my heartbeat to demonstrate the problem. Channel one (blue line) is from channel 1 of the master amp. Channel 2 (red line) is from channel 5 of the slave amp (#21 overall). Both are recording from my left index finger referenced to my right index finger. 12 runs total.
Unless I press "Set Config" the (mis)alignment between amps stays the same in sequential runs. When I press "Set Config" there seems to be a random misalignment that is generated between the amps.

I dont think this is affected by my other issue (see: "Irregular Timing with 2 g.tec amps"), because the lag between amps is constant within runs as well.

Any suggestions?

Thanks in advance,
Andrew

I have never heard about this problem, even though we and many others have been using BCI2000 extensively with synced g.USBamps.

My best guess is that this issue has something to do with the particular configuration you are using. I would try to switch the order of the two amps, including switching Master and Slave, and upgrade to the latest version of BCI2000 and the g.USBamp drivers.

Gerv