The sample should use an 11468 Hz sample rate, and is converted to 4 bits. A sample bank is 16384 bytes long, minus $60 (hex) header bytes, which gives 16288 bytes. There are two 4 bit sample in a byte, which means you have room for exactly 32576 samples. Then you can divide one by the other: 32576/11468=2.84 seconds.

Thank you