There are a couple of gotcha's to remember when using an SCXI-1122. First, this module has a single-amp, single-filter configuration. This means that within a scan, only one gain may be set for all channels. Furthermore, depending on the filter setting, your scan rate may be greatly inhibited. The proper method to use when scanning an 1122 is to scan one channel many times and then reconfigure and go to the next channel. Etc, etc. Also, remember that the 1122 has mechanical relays that are subject to wear out if not scanned properly. The SCXI-1102B does not suffer from these issues because it has 32 seperate filters and amplifiers.