I encountered weird thing yesterday. I'm not sure it's new, but I think it must be, because it would happen to me before. I think.
So .. I'm in debugger, just assembler window. F10 should bring me to next instruction, right ? So I'm stepping, stepping .. and suddenly it throws me away, and stops on break point far far away, as if I pressed 'go' instead of step. Tried again after rebooting the image, happened again on the same spot. I checked the history, and sure enough, DLI was being fired right when I pressed F10 the last time.
In my case DLI was being fired on every text line, and I was debuging slow code, so it was really a problem. Those DLIs fired all the time. I could get around it by waiting for vertical blank on the start of the routine, and then finding the bug before VB was over.