Connection issues (or not?)

[Vixen99]

Hi,

I've been using my Muse 2 for less than a month now. I realize from the graphs that, when used with Mind Monitor, in 10 minutes I get at least one disconnect - which is immediately resolved with a reconnect - and in the graph it is marked as "Bad Fit - Good Fit".
Should I be concerned about the quality of the device or is it normal for this to happen to many with Bluetooth?
The signal from the front and rear sensors is generally good - I've started using an EEG gel on my skin which has greatly improved the connection, which otherwise was often poor, especially on TP9 and TP10. With the gel I immediately get a stable connection everywhere.

I meditate with my eyes open (if that changes anything).

Thanks!

[James]

How you use the Muse won't affect the bluetooth connection. Even if you remove the headband and leave it on a table, it should remain connected.

What's the make/model of your device? There are a number of Huawei devices which have known issues with the Muse and Interaxon does not support using any Huawei device with Muse.

Do you have any other bluetooth devices connected at the same time when using the Muse? E.g. wireless earbuds/headphones. This can reduce the available bandwidth for the Muse data.

[Vixen99]

No, it's the only device. My phone is a POCO X3 PRO (XIAOMI MI). Power saving is turned off on the app to avoid problems.
MUSE-A20B.
MODEL: MU-03
4107-HYYT-A20B

[James]

I've not heard of any problems with that particular phone. Please email me a 5 minute recording with the "Recording Interval" in settings, set to "Constant" and I'll see if there are any data issues. After, set the "Recording Interval" back to the default "1 sec".

[Vixen99]

Shall I meditate (or in any way use the headband on my skin) on that recording or just leave the device connected to the bluetooth? I can also try the device on another phone that I've, an Asus Zenfone 3.

[James]

Put it on, and give me 5 minutes of eyes closed relaxation, then the RAW EEG should be nice and flat and it'll be easier for me to notice artifacts.

[Vixen99]

Ehy, I tried again.
I tried it on a different phone (the Asus Zenfone) but there it got weird. I tried it a couple of times and the result was the same: it keeps me telling "NaN (Not a Number) data found" (see the CSV.zip: https://drive.google.com/file/d/1_MK81j ... sp=sharing )
Tried again (and a couple of times, just to be sure) on the POCO, and this time it seems I got nothing wrong, no Good fit/Bad fit (CSV-zip: https://drive.google.com/file/d/1Qobvw3 ... sp=sharing )
I closed my eyes but probably didn't put too much effort. I cleaned the sensors with alcohol before trying. I reinstalled the app on both phones.

What do you think?

[James]

You definately have a problem here.
In the first 5 minute poco recording you sent, it cut out twice, for 11.5 seconds each time.

I don't see any issues with the data when it is recording, but the fact that it totally disconnected with 50% battery remaining is worrying.

The NaN data from the Asus Zenfone is something I've seen before on Huawei products. It means they're using a low quality Bluetooth chip that can't handle the amount of data that the Muse puts out.

Both your devices are budget chinese phones, so it's likely that they are the issue rather than the Muse; but to be absoutely sure, I would like you to test the Muse device on a phone that I know to be good. Do you have any friends with an iPhone, or Google Pixel (any model), who could run a test. I will send you a code, so you can install Mind Monitor for free on their device for the testing.

If you get errors with an iPhone or Google Pixel, then the Muse itself is likely faulty, though I think this is very unlikely as I've never myself seen an actual faulty Muse, only ones with dirty contacts that need cleaning

[Vixen99]

Does this argument apply even though the second time with the POCO, while trying twice always for five minutes, it doesn't seem to disconnect any time?

However, when I received the device I was a little worried about these spots in this sensor: https://drive.google.com/file/d/14Kyg2_ ... sp=sharing
but it seems to me that there is no problem with the front sensors, no?

Thanks for the help, I will try to find one of those two phones. Maybe a friend of mine has an iPhone that she doesn't use.

[James]

Dirt on the sensor strip won't cause Bluetooth to disconnect or NaN data.
With the new Muse-S you can unclip the module from the headband completely and it'll still produce data. It'll make non-sense data, but still data.