Erase function not erasing completely

Question

Hello everyone,
While testing something else I noticed that the erase function is not wroking as it should. Normally when you erase you just have to swipe the cursor, over the area to be erased, once and the pixels are gone. Now when I erase pixels are left behind, it's not a clean erase.
Attached is a screen shot of what I am talking about. This is just one pass with the cursor, if I want to delete this entirely I would have to go over it again and again, muh like using a realy erase on graphite.
Do you have any idea what is going on, what setting got changed??
Thank you,
J

Answer 1

I knew I was going to forget to add tha tI had already checked the opacity and flow, they are both set to 100%. They blend mode is set to normal, this one I did not check.
I did figure this out though...
Previously I had checked my brush settings (right clicking with the brush/eraser command active). The hard round brush option had the blue square around it, so I figured that was the brush I was using... I was wrong. Though the 'Brush' command was using a hard round brush, the 'Erase' command was using a Square Pastel brush, I have no idea how it got there.
So, even though the blue square was around the hard round, the pastel brush is what was really being used.
Anyway, thank you very much for the response, it is appreciated.
J