Below is a link to the current firmware version for the Venue 2 receiver. This is a zip file, after downloading extract it into a temporary folder. Use the Wireless Designer program to update firmware, instructions are found here.
Note: This is a link to the Wireless Designer firmware update file, which bundles the latest firmware for both Venue 2 and the DR receiver. Wireless Designer will know you are updating a Venue 2 system and automatically choose the right firmware images from the file.