I received an audio book on cd yesterday and when I inspected the CD's I felt they were in below fair condition. I would not have posted them. I sent the sender a message stating that I had not tried to play them but the condition was poor enough that I do not think I would post them.

She replied that they played for her and that how she received the from PBS. I have not complained in the past and I dont want to make a big thing out of it but I dont want to lose two credits for a audiobook that I do not feel is repostable. Is that being to picky?

What precisely makes them below fair condition?  The condition of the box?  Scratches?

Per the condition guidelines, as long as they play with no more than 3 minor skips, they are postable.  She doesn't have to return your credits and you can post them again.

The discs are scuffed and scratched, I have not played them yet. Maybe I should listen to them right away to make sure that I can repost them. I foolishly made the assumption that I would not be able to repost them.  

How scuffed or scratched they look is no indication of how well they'll play, so I'd say yes, you're being too picky.  I listen to audio books every day and have listened to many that play perfectly even though they look very scratched up.  On the opposite end of the spectrum, I have bought a brand new audio book in a store, still factory sealed in shrink wrap, showing no visible scratches or defects, which had a skip on it.  The only way to tell is to play it.  From the help docs: 

• Audiobooks do NOT have to include the box that enclosed the individual cassettes/CDs
  • The audiobooks should be packaged well if the box is missing, to prevent damage by USPS en route
  • Audio CDs must be shipped in a way that will protect them from scratching (CD cases/DVD cases work well), if the original box is missing
• Audiobooks must be playable to be swapped here, without more than three (minor) skips.

One would think that the very FIRST thing you would do is sample random tracks of the CDs to see if they are playable, if you weren't going to listen to them right away.  You've, maybe, upset a sender for no reason.

Different players can play CDs differently. I would use the newest CD player that you have including cars, computers and DVD or Blu-Ray players. An older CD player may not be able to read the CDs as well as the newer ones. If one member uses a PC DVD drive and doesn't hear any skips, the next person could use an older one and hear skips. There are products available to help remove skips from CDs.

funny thing Sarah,  my old mini-van's CD player actually plays CDs that we can't get to play on our computers or newer players!  Go figure!

Vehicle players are usually made better than any stand alone device because they need to be made good enough to handle playing through road bumps and humps.

Though the look of a DVD doesn't tell how well it will play, one that is badly scratched runs a higher risk of having skips on the receiver's player. Though the sender can say they didn't have skips and not return the credit, the receiver can still mark it as a problem swap - unresolved because they do have skips with it in the condition they received it in (if the book does have the skipping, not just because of looks). Might be best to swap disks that have a lot of scratches in the Bazaar where one can explain the condition and let the receiver request them knowing what they might be getting into.