Check the controller chip that install the LED panel, if are ICN2038S or FM6126, those are not compatible Smartmatrix because these chips require three clock pulses by Latch.
When you order LED panels, ask to the seller for the controller chip that install, and avoid those mentioned.
I order currently all my LED panels with FM6124 controller chip, and work perfectly, also tested with ICN2038 and some more references.
Currently I have only detected incompatibility with ICN2038S and FM6126 controller chips. If you download the datasheet can you see the differences to manage the Latch signal.