modulo to cycle though a compute buffer not working as expected - unity3d

Question

The Setup
In my compute-shader I have a StructuredBuffer that is storing an amount of colors. There is also an int variable storing the amount of colors in total ( _colres ). From another script a node tree is dispatched into the shader every frame. The amount of nodes changes dynamically. Because of that the points buffer containing the nodes is at a fixed size of 8192 that the amount of nodes never exceeds.
The Problem
When I'm now trying to draw the points I am storing in the points buffer, oddly enough only every third color is displayed, starting at index [0] (tested for up to 12 colors -> [0],[3],[6],[9]).
Result[pointsBuffer[id.x].xy] = colorsBuffer[id.x % _colres];
What I tried
I used the fmod() function instead but was presented with the same result. Individually targeting stored colors by hard-coding the index has worked so my guess would be that the colors buffer is not the problem. Maybe it has something to do with all the empty spaces in the pointsbuffer but I could't figure it out.
The Question(s)
Is there a fundamental problem I am overlooking?
Is there some other simple way to cycle through the indices of my colorsbuffer that works in this scenario?
Detailed Information
System:
Unity Version 2021.2.12f1 using the HDRP on MacOS Monterey 12.2.1
Compute-Shader
#pragma kernel DrawPoints
// texture
shared RWTexture2D<float4> Result;
int _texres;
int _colres;
// buffer
StructuredBuffer<float2> pointsBuffer;
StructuredBuffer<float4> colorsBuffer;
[numthreads(64,1,1)]
void DrawPoints (uint3 id : SV_DispatchThreadID)
{
if ((pointsBuffer[id.x].x * pointsBuffer[id.x].y) > 0) Result[pointsBuffer[id.x].xy] = colorsBuffer[id.x % _colres];
}
C# Setup
public differentialGrowth diffGrowth;
int texResolution = 4096;
int colorAmount = 12;
RenderTexture settingRef;
Material target;
ComputeShader shader;
RenderTexture outputTexture;
ComputeBuffer pointsBuffer;
ComputeBuffer colorsBuffer;
int pointsHandle;
void Start()
{
outputTexture = new RenderTexture(settingRef);
outputTexture.enableRandomWrite = true;
outputTexture.Create();
// INIT
pointsHandle = shader.FindKernel("DrawPoints");
shader.SetInt("_texres", texResolution);
shader.SetInt("_colres", colorAmount);
int stride = (3) * 4; // every component as a float (3) * 4 bytes per float
pointsBuffer = new ComputeBuffer(8192, stride);
stride = (4) * 4;
colorsBuffer = new ComputeBuffer(colorAmount, stride);
shader.SetTexture( pointsHandle, "Result", outputTexture );
target.SetTexture("_MainTex", outputTexture);
Color[] testColors = new Color[colorAmount];
testColors[0] = new Color(1, 0, 0, 0); //red _ yes
testColors[1] = new Color(0, 1, 0, 0); //green
testColors[2] = new Color(0, 0, 1, 0); //blue
testColors[3] = new Color(1, 1, 0, 0); //yellow _yes
testColors[4] = new Color(0, 1, 1, 0); //cyan
testColors[5] = new Color(1, 0, 1, 0); //magenta
testColors[6] = new Color(0.5f, 0, 1, 0); //mix6 _yes
testColors[7] = new Color(1, 0.5f, 1, 0); //mix7
testColors[8] = new Color(0.5f, 0, 1, 0); //mix8
testColors[9] = new Color(0.5f, 0.5f, 1, 0); //mix9 _yes
testColors[10] = new Color(0.5f, 0.5f, 1, 0); //mix10
testColors[11] = new Color(0.5f, 0.5f, 1, 0); //mix11
}
void Update()
{
pointsBuffer.SetData(diffGrowth.nodes.Points);
shader.SetBuffer(pointsHandle, "colorsBuffer", colorsBuffer);
shader.SetBuffer(pointsHandle, "pointsBuffer", pointsBuffer);
shader.Dispatch(pointsHandle, 128, 1, 1);
}
private void OnDestroy()
{
if (pointsBuffer != null) pointsBuffer.Dispose();
if (colorsBuffer != null) colorsBuffer.Dispose();
}
}