# Unexpected repeating pixels

**URL:** <https://wled.discourse.group/t/unexpected-repeating-pixels/1942>\
**Category:** Hardware\
**Created:** [January 2, 2021, 6:58pm UTC](https://wled.discourse.group/t/unexpected-repeating-pixels/1942 "2021-01-02T18:58:08Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Evil-tom](https://avatars.discourse-cdn.com/v4/letter/e/58f4c7/32.png) [@Evil-tom](https://wled.discourse.group/u/Evil-tom)\
**Post date:** [January 2, 2021, 6:58pm UTC](https://wled.discourse.group/t/unexpected-repeating-pixels/1942/1 "2021-01-02T18:58:08Z")

</div>

Hi all.  
I’m having a strange problem with two strings of LEDs.  
I bought a 200 LED string of [these](https://www.aliexpress.com/item/1005001670784973.html) for my Christmas Tree. Cut of the basic controller they came with and connected them to a D1mini flashed with WLED. They worked perfectly after changing the colour order and the tree looked brilliant.  
The only problem was that the 200 LEDs were a little short for my 7ft tree and the loops of lights were a little far apart. So I went back to the same listing and bought a string of 100 LEDS. Again cut off the controller and connected the new string onto the end of the old string.  
I should say that the 200 long string turned up as two bundles of 100 soldered together. There are also other solder joins along the length of the string.  
I expected pixel 1 of the second string to become pixel 201 of the new bigger string and to just have to adjust the total number of pixels in the settings.  
But pixel 1 (physically number 201) of the new string is mirroring pixel 1, It’s like they’re in parallel rather than in series.  
I tried playing around with settings and segments but no joy.  
I’ve tried flashing a very basic Arduino Pixel test sketch that just lights the first three LEDs in red, green and blue respectively. This caused 1-3, 101-103 and 201- 203 to light up.  
I then just put wled back on it and set the pixel count to 300 and its doing the same - 1-200 are fine, 201+ mirrors pixel 1 onwards  
I have no idea what the actual chips are, the listing claims WS2812B and SK6812. Are there pixels that need to be assigned an unique identifier before use?  
I’m really confused!!

---

<div class="post-metadata">

**Author:** ![tonyno](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/tonyno/32/242_2.png) [@tonyno](https://wled.discourse.group/u/tonyno)\
**Post date:** [January 2, 2021, 10:14pm UTC](https://wled.discourse.group/t/unexpected-repeating-pixels/1942/2 "2021-01-02T22:14:41Z")

</div>

Some lights have been found to act like that. No way around it AFAIK.

---

<div class="post-metadata">

**Author:** ![Gerrit42](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/gerrit42/32/1475_2.png) [@Gerrit42](https://wled.discourse.group/u/Gerrit42)\
**Post date:** [May 15, 2021, 9:32am UTC](https://wled.discourse.group/t/unexpected-repeating-pixels/1942/3 "2021-05-15T09:32:51Z")

</div>

hello  
may be u use a second output  
maybe that helps  
does every string work on its own correct ?  
so maybe !