ActiView103 sending multiple LSL streams

[astovall]

Hello,

I'm using an Active3 system and ActiView103 w/ native LSL support to stream data to Lab Recorder 1.16.4 on a Win11 desktop. When I start ActiView, the single "ActiView" stream appears in Lab Recorder, as expected. If I start saving in Lab Recorder, the output window gives the expected series of confirmations:

Opened the stream ActiView
Received header for stream ActiView
Started data collection for stream ActiView

However, these statements appear MANY times, instead of just once, indicating that multiple streams are being detected. The output eventually states:

WARN| Found multiple streams with name='ActiView'. Cannot recover unless all but one are closed.
ERR| Stream transmission broke off (Input stream error.); re-connecting...

If I stop saving in Lab Recorder and open the .xdf file, it shows a <1x97> cell array containing 97 "ActiView streams", with no data saved (time series is empty). I also noticed that if I open BrainVision LSL Viewer 0.9.5 and connect to the ActiView stream, no data appears.

After playing around with things some more (essentially opening/closing the software and starting/saving in different orders), I did eventually get it to work as expected (Lab Recorder output confirmed just ONCE that it opened the stream "ActiView", the data appeared in BrainVision, and the .xdf contained only a single ActiView stream with the time series populated with data). However, frankly, I'm not sure what exactly I did to get it to work and can't recreate it (every time I tried after that, it once again did NOT work properly).

Any help would be appreciated, thanks!

[Coen]

Does it work with the BrainVision LSL viewer ( https://labstreaminglayer.readthedocs.i ... ewers.html ) ?

Which errors do you see in ActiView (popup messages and/or error counters in the lower right corner) ?

Best regards, Coen (BioSemi)

[astovall]

No data appears if I connect to the ActiView stream in BrainVision. However, the one time I got everything to work as expected, data DID appear in BrainVision.

After Lab Recorder gives the error that it found multiple streams with the same name, if I let it keep running, eventually ActiView gives the following error:

Error 8002 occurred at Synchronization
Possible reason(s):
Intermittent data loss (check optical fiber)
or
USB driver not properly closed on exit (restart LabVIEW and ActiVIEW)

Once that error appears, the error counter quickly increases in the lower right corner of ActiView for both "Corrupt" and "Lost" counts (in my last test that I ran, it showed 4 Corrupt error counts and 3653 Lost error counts before I stopped it). The computer also seems to freeze up around this same time.

[astovall]

A little more detail to my last post:

If I start ActiView then open BrainVision and click “Connect”, the “Select LSL streams” box appears. It initially says “1 regular stream(s) available” (with ActiView listed), but then quickly jumps up to anywhere between 70-250 regular stream(s) available and continues to fluctuate every ~1 second. However, while the number is fluctuating, only one ActiView stream continues to be shown for selection.

This seems to be the same thing I’m seeing in Lab Recorder, where only one ActiView stream is shown, but somehow many streams are being sent.

I’ve tested on two different Win10 desktops and the result is the same for both. I’ve also tried disconnecting from all LANs with no difference in outcome.

[Coen]

I have made some changes to the LabVIEW code that should prevent the multiple streams. Please email to info@biosemi.com and I will sent you a download link for a preliminary version of the upcoming ActiView 104.

Best regards, Coen (BioSemi)

[astovall]

That sounds great, thanks! I sent an email to info@biosemi.com.