The 64/128/192 bytes you do receive indicate some pointer/buffer problem since the USB FIFO buffers are 64 bytes. Try identifying any pointer/buffer handling and make sure that the interrupt service routine doesn't interfere with the buffer pointers ...

If you are building a card reader, be aware that all contact points must be in high impedance mode until the card is fully inserted into the reader. Otherwise some inputs will be shorted, voltage applied to the "wrong" inputs and so on. There is usua...