I have no problems playing burned DVD-R discs on my A1 or XA1.
I strictly use Verbatim brand discs and will not burn faster than 4X (Burning speed is a major factor when it comes to compatibility issues). After doing this for seven years now, I have tried every other brand of discs, and Verbatim brand have been the most reliable; I have some now approaching six years old that still play fine. My second choice would be Taiyo Yuden brand. Both can be purchased on line for very reasonable prices.
I use AnyDVD and DVDClone (both by Slysoft) for creating backups, and my burners are Plextor and BenQ brand.
For serious archival material, I rely on Panasonic brand RAM discs. I have never had one fail in seven years.
Hope this helps