ECG data acquisition starts immediately when you press "Start." However, On Android 15 the amount/frequency of data received is about 10 times less than on Android 14 because of this issue with the bluetooth.
There's a parameter called sampleRate, which is represented as dataPerSec on the graph. For ECG, it's set to 500, meaning we need 500 data points to consider one second to have passed.
Since the data is coming in slowly, and some of them is lost due to delays, the rendering is random. If we don't receive 500 data points, say only 250, the time appears to slow down because of the hardcoded link to this sampleRate.
Unfortunately, this is not something we can fix without the fix of Android 15.
