That's pretty bizarre. I use both Audacity and WavePad and have never noticed a speed issue. I record from both vinyls and tapes. I used to record from my line-in port, but then I got a little amplifier from ARTCessories so I could have a 24 bit A/D converter. And it then feeds into my computer as a USB sound card. Neither lash-up exhibited the speed issue you described.
I am even having trouble hypothesizing a way to get the behavior you are having. How about a little lengthier description of the process you use. Maybe there is a clue somewhere along the way.
Bob Hickling in Princeville, HI