Pixma mp 780 printing too slow

[Jim_20]

Hi there
I own a Canon Pixma mp780 that is about 7 years old. It used to print very quick and quicker for back & white. It just started to slow down dramatically. I fed a A4 booklet that contained about 10 pages or so into the top of the machine and some pages had printered out quick but the majority of them had printered out very slowly eg taking up to 2 to 3 minutes to print an A4 page in black or white. Can you tell me what the problem is.
Thanks

 

[saint19]

Do you check the resolution of the printing?

 

[Jim_20]

The resolution is the same since I bought. It's never been changed. I don't think it's that I was looking more into the computers memory or maybe the printing head, those sort of complexed areas. I was hoping that someone may have tips in rectifying the problem if it was to do with those 2 areas.
Thanks