Washing machine slow to drain and clo...

My fisher & paykel smart drive is about 10 years old and over the last month it is taking ages to drain out water between cycles. A normal cycle now taking about 2 hours. Also the clothes are coming out with scrud over some of them and not overly clean. I opened up the fabric softener (which I never use by the way) and it was really filthy inside so gave it a bit of a clean but obviously not enough. I also pretty much only use cold or cold/warm cycles. Could it just be that my machine needs a good clean/water blast or is something stuck in it.