Problem receiving data from bluetooth at very high speeds with Bluetooth Serial - flutter

Question

I'm using the flutter_bluetooth_serial 0.4.0 package, it has a listen function that receives a function that returns the reading of the sending of a string (List Uint8), but for my case I need to carry out the communication at a very high speed, and when this happens it does not understand where the end of a string is and joins overflow with 230 bytes and shows as if it was a single string, I tried to solve this in several ways, but I only managed to receive a complete string (18 bytes) when I slow down of transmission. I would need to read 40 bytes at a time regardless of '\n' or anything, I would have for this case maybe read byte by byte to validate the message and not a Uint8. In this case the input is a Stream and I would have to transform it into a Stream or something that makes me receive 40 bytes at a time regardless of the speed. Most of the time, a message comes together with another, and this could not happen in this transmission.
Here is the code snippet I get the data:
_dataSubscription = connection.input!.listen(_onDataReceived);
void _onDataReceived(Uint8List data) {
print('Data incoming: ${ascii.decode(data)}');
// Allocate buffer for parsed data
var backspacesCounter = 0;
for (var byte in data) {
if (byte == 8 || byte == 127) backspacesCounter++;
}
var buffer = Uint8List(data.length - backspacesCounter);
var bufferIndex = buffer.length;
// Apply backspace control character
backspacesCounter = 0;
for (int i = data.length - 1; i >= 0; i--) {
if (data[i] == 8 || data[i] == 127) {
backspacesCounter++;
} else {
if (backspacesCounter > 0) {
backspacesCounter--;
} else {
buffer[--bufferIndex] = data[i];
}
}
// print(backspacesCounter);
// print(buffer);
// print(bufferIndex);
}