Real time chart issue

I know this issue discussed many times but I could not find a solution for my case.
I created this class

import Foundation
import Charts

class SignalChart : LineChartView, ChartViewDelegate
{
@IBInspectable var signalName:String = ""

required init?(coder: NSCoder)
{
super.init(coder: coder)

self.gridBackgroundColor = NSUIColor.white
self.xAxis.drawGridLinesEnabled = false;
self.xAxis.labelPosition = XAxis.LabelPosition.bottom
}

func update(data: [ChartDataEntry])
{
let chartData = LineChartData()
let dataset = LineChartDataSet(values: data, label: signalName)

dataset.drawCirclesEnabled = false
dataset.colors = [NSUIColor.red]
dataset.mode = .cubicBezier

chartData.addDataSet(dataset)
self.clear()
self.clearValues()
self.data = chartData

self.data?.removeEntry(data.first!, dataSetIndex: 0)

self.notifyDataSetChanged()
}
}

So actually this is working. When my dataset is big enough, it starts to feel like a signal reader which I am trying to achieve. My problem is the below. At one point, which is not fixed(sometimes it happens in a second or it happens after 5 seconds, but it happens). So i do not think it is because of the sample size since it does sometimes when it is full or after a while it is full, or not full at all.

This is when it is working properly.

And this what happens after a while

Any ideas?

Start with the SignalChart.update(data:) entry point and its LineChartView, LineChartData, and LineChartDataSet usage. Reproduce the transition between the two linked chart states while varying dataset size and update timing; done means the triggering conditions and expected chart behavior are documented, with no repository file or test named in the issue.

Written by the indexing model from the issue text.