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Android 10 L2CAP connection IOException timeout Wii Balance Board

Background
A long time ago I was tasked with making a android app for the Wii Balance Board, after some screwing around I found that android no longer supported L2CAP. More research lead to understand that it was being re-added in Android 10. With Android 10 out I've been trying to give it a crack now.
Problem
So my simple goal at the moment is to create a connection with the Wii Balance Board.
My approach for connection is:
Start discovery
Add discovered bluetooth devices to list
When you click on a device it then tries to open a socket as such:
bluetoothSocket = btDevice.createInsecureL2capChannel(port);
As mentioned on the WiiBrew site I'm using psm value 0x13 for input and 0x11 for output.
I then use bluetoothSocket.connect and proceed to receive a IOException (timeout error)
I've also tried using both createL2capChannel and createInsecureL2capChannel with same results
I was able to successfully pair to the device using btDevice.createBond() and then using the phones BT address backwards for .setpin() and the Wii Balance Board simply acts as a "dumb" input device. (not sure if pairing is needed/good idea)
The above is a simplified flow of how I'm trying to connect. I've also tried using BalanceBoard.java from Paul Burton's fitscales repo updating all of the old bluetooth code, again I still get the timeout.

Have you looked at the bt_stack logs?
Here is mine from trying to open a socket with a wiimote:
04-05 12:25:04.949 E/bt_stack(4895): [ERROR:btif_sock_l2cap.cc(244)] SOCK_LIST: free(id = 4) - NO app_fd!
04-05 12:25:04.949 I/bt_stack(4895): [INFO:btsnoop.cc(323)] clear_l2cap_whitelist: Clearing whitelist from l2cap channel. conn_handle=65535 cid=65:0
04-05 12:25:04.949 E/bt_l2cap(4895): L2CA_FreeLePSM: Invalid PSM=19 value!
04-05 12:25:40.141 I/bt_stack(4895): [INFO:btsnoop.cc(323)] clear_l2cap_whitelist: Clearing whitelist from l2cap channel. conn_handle=1 cid=66:64
04-05 12:25:55.736 I/bt_stack(4895): [INFO:btsnoop.cc(323)] clear_l2cap_whitelist: Clearing whitelist from l2cap channel. conn_handle=2 cid=67:65
I believe this is where the problem lies, Im only a novice so Im not sure what can be done about it. I know the old ways of connecting passed the fd as a parameter to the bluetooth socket constructor but I dont think this is possible anymore

BLE Device dissonect after receive Notifications (BLEGattException Status = 0x8)

My BLE server permanently measures a sensor value and sends a notification with 20 byte user data after each measurement. The goal is to generate as much throughput as possible.
On the client side, the value sent by the server is received and processed.
rxBleConnection.setupNotification(setDescriptorEnableNotification(characteristic))
.flatMap(notificationObservable -> notificationObservable)
.observeOn(Schedulers.newThread())
.buffer(1)
.subscribe(bytes -> {
onNotificationReceived(bytes, buffer);
} , throwable -> {
// Handle an error here.
onNotificationSetupFailure(throwable);
}
);
If I set the Connection intervall to 11.25ms, I receive all values. However, if I set the connection interval to 30ms, I receive a few values ​​and then the connection is closed.
In the Android Log i see the followed message:
BleGattException status=8 (0x8),
bleGattOperationType=BleGattOperation{description='CONNECTION_STATE'
Why is the connection interrupted and what is the trigger?
With the help of a BLE Sniffer this is not recognizable. The set connection parameters are accepted and the transfer begins. Suddenly the transmission ends and the error message appears.
Update:
BLE Sniffer screenshot has been added:

30ms, this is connection interval you set in server or android?
Btw, on android you can set speed mode
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
mBluetoothGatt.requestConnectionPriority(BluetoothGatt.CONNECTION_PRIORITY_HIGH);
}

Error 8 means the connection timed out. There is nothing wrong on the Android side. The problem is with the communication between the two Bluetooth controllers. If you have a sniffer then you should be able to see who is the one that fails to send packets.

Here is an Image from BLE Sniffer.
BLE Sniffer

I have the similar problem. On Android 7.0 there were two ways to keep connection:
1) If devices are bonded and there is a charachteristic reading callback with constant thread of packets. If there are no packets by some time, then connection fails.
2) If devides are not bonded, but I do TXCharacheristic.read every few seconds. If don't do that some time, then connection fails.
But now in Android 7.1.2 this way doesn't work.
May be the first way will work for you.
On your Android device you should make bonding, on your kit you should handle this bonding.
On Nexus 6P and Samsung S7 it doesn't work anymore, but I didn't try it on the other devices.

I suppose, you have min connection interval 7.5 on your BLE kit, but now it is deprecated on Android.
Try to set min connection interval to 11.25 on your BLE kit and set connection priority
gatt.requestConnectionPriority(CONNECTION_PRIORITY_HIGH);
where CONNECTION_PRIORITY_HIGH = 1
in onConnectionStateChange.
It had worked for me when I had changed min connection interval in my nordic from 7.5 to 11.25.

modify android.server.BluetoothService.java to update cached service_channel_no of paired device to open multiple connections to it(on mul. channels)

I am stuck at a place where my Android Phone(Samsung Galaxy) has to open 2(or more) connections to my PC(server) which is a paired device. For this purpose, I start SDP server on PC with UUID : 00001101-0000-1000-8000-00805F9B34FB and channel 2, after the first connection I unregister the SDP service on the PC and register it again on channel 3(and same UUID) and expect my android phone to 'connect' to it for establishing the second bluetooth connection. The second one fails.
The problem as I have figured out is that because of the pairing, the channel num and UUID of the device for the 'BluetoothSocket.connect' are serviced from cache and are not being updated, so my SDP change in channel num on the server side is not visible here as it still tries to connect to channel 2(old one).
A workaround of this problem(found after a lot of frustrating attempts) might be to change the android.server.BluetoothService.java file, by introducing
updateDeviceServiceChannelCache(addr) before returning in the getRemoteServiceChannel() and fetchRemoteUuids() so as to update the channel number at each func call.
The above solution may well be wrong, please pardon me for that. If it is correct please suggest any further changes and how to make this change permanent in eclipse, or in other case(wrong solution), the right way of doing this.
Note: I have android 2.3.5 and the requests from the device are actually from the browser that I forward to the PC. I want them on separate channels.
thanks.

Bluetooth drivers fail to install pairing my Samsung phone

I'm currently working on an Android application based on Bluetooth Chat sample. The code seems to work but when I try to pair my android device (a Samsung Ace GT-S5839i) with my laptop, some drivers fail to install.
In the device bluetooth services list I can see BluetoothChatSecure and BluetoothChatInsecure services but when I try to connect my phone to my laptop I have a connection error.
This is my first time doing any Bluetooth development, and I can't figure out what happens.
EDIT:
Actually I have several errors:
08-11 01:34:49.140: E/BluetoothChat(29847): + ON RESUME +
08-11 01:34:49.187: E/BluetoothEventLoop.cpp(1510): onCreateDeviceResult: D-Bus error: org.bluez.Error.AlreadyExists (Device already exists)
08-11 01:34:49.203: E/DTUN_HCID4(29886): No device pointer found for peer! Ignore Error = true. Ignoring error...
08-11 01:34:49.421: E/(29869): ****************search UUID = 87fa***********
08-11 01:34:50.179: E/BluetoothEventLoop.cpp(1510): event_filter: Received signal org.bluez.Device:PropertyChanged from /org/bluez/29886/hci0/dev_70_F1_A1_B7_61_A8
08-11 01:34:54.304: E/BluetoothEventLoop.cpp(1510): event_filter: Received signal org.bluez.Device:PropertyChanged from /org/bluez/29886/hci0/dev_70_F1_A1_B7_61_A8
P.S.
Does anybody know why Windows tried to install two Bluetooth Peripheral Device without finding the right drivers when I used the default uuid?

I finally set up a bluetooth secure connection between my phone and my laptop. These are the required steps:
First, I set up a Bluetooth Icoming COM port in my laptop
Secondly, I changed my uuid according to the [android documentation][2]
Hint: If you are connecting to a Bluetooth serial board then try using the well-known SPP UUID 00001101-0000-1000-8000-00805F9B34FB.
Then I enabled the SSP service in my phone so I was able to get the
Standard Serial over Bluetooth link working
Finally, I open a serial connection with the Icoming COM port through
a Hyperterminal (like putty)
I hope this is helpful to someone.

Cleaning up failed UUID channel lookup

when opening a bluetooth rfcomm socket via the UUID method ( the other method ( using reflection ) in here http://code.google.com/p/android/issues/detail?id=5427 ) - I sometimes get the following error ( after successfull connections ) and the socket is not opened:
E/BluetoothService(21847): Received ACTION_UPDATE_SERVICE_CACHE00:0B:CE:01:2E:00
D/BluetoothService(21847): updateDeviceServiceChannelCache(00:0B:CE:01:2E:00)
D/BluetoothService(21847): Cleaning up failed UUID channel lookup: 00:0B:CE:01:2E:00 00001101-0000-1000-8000-00805f9b34fb
had no luck with google on this one - has anyone here a clue whats going on and how to prevent that?
Update:
for people running into the same problem - possible solutions:
advice the users to reboot the device if we run into that state (
very bad UX )
use the reflection method ( dirty but works most of the time )
I am still open for new Ideas ;-)
I stick to #2 at the moment - but waiting for a better solution.

It seems that the message is the consequence, not the reason. If a serial port emulation service is not found on device the connection will obviously fail.
Update
After reviewing code everything seems ok. So my questions are: Do the random errors occur with same device o with different devices? If the occur with different devices, the devices might have not registered the SerialPort service. Is device previously paired? In case of the error ocurring randomly with same device? Are you using the connection class concurrently? You have not protected the methods against concurrent access. You have not protected either against succesive connects. If you try to read/close a stream after a second connect it will fail (the socket object has changed).
It seems ok. The random error occurs with same device? If this is the case, are you using concurrent use of that class? In first case