MrMcChicken:
The schematic of the Matrix is really simple. There are 5 rows with 7 led each. The rows have a common gnd ant the columns have a common anode.
I use 330R resistors. Everything is connectet to the digital pins of my Arduino UNO.
If you can't tell us what you're doing, nobody can help you and this thread is an exercise in frustration. How is the matrix connected to the Arduino?
Everything is connected to the digital pins? Directly? so rows and columns? The Arduino outputs can only sink or source 40mA, which is not enough to drive a full row (or column) as you can.
If you have resistors on the rows and columns, you are splitting your current among whatever LEDs are on on that row (or column) so the brightness of each row (or column) will depend on how many LEDs are on and will not be consistant across the matrix.