I dare say the player couldnt determine an A side from a B side if its life depended on it. Your problem is elsewhere, such as not lowering the armature lifter fully, or a dysfunctional one. A or B Is basically just a matter of what is printed on the label. If the discs were all stored in a hot environment unsleeved, for, well, a very long time, they may all have developed a permanent dish, and no longer be flat, but that to would be very unusual. The disk has to lay flat on the platter to "grip" as you put it.