How to clear a single checkbox with button click?

Hi Patrick (or anyone else in the mood to chime in),

I can’t seem to dynamically uncheck the checkboxes (for instance on reload of sc or click on button) that are in my table. What am I missing here?

I have this check all checkbox:

<input class="form-check-input" type="checkbox" value="" id="allcheck" name="allcheck">

And I have a checkbox in my table:

<td><div is="dmx-checkbox-group" id="group1" class="checkbox-group">
<input class="custom-control-input" type="checkbox" 
dmx-bind:id="'incomingorders'+$index" dmx-bind:value="id" 
dmx-bind:checked="allcheck.checked" 
dmx-on:updated="checked ? arr_orders.addUniq(id) : arr_orders.remove(id)"></div></td>

Now on clicking this button the check all does uncheck, but the checkbox in the table does not uncheck (I have tried multiple mentioned sollutions here):

<button id="btn2" class="btn" dmx-on:click="allcheck.select(false);group1.setValue([])" onclick="$('[name=group1]').prop('checked', false)">uncheck</button>

It would be great if anyone could point me in the right direction here.

bg Jelle