A few things to consider:
A) Make sure that the Digital input format is set to the type that corresponds with your signal source. Choices are AES or SPDIF Coax. The default is AES, if your source is SPDIF, you need to change the following things on the card. Use jumpers JP701 and JP702 to set the mode, and switch SW200 to set the format. In the case of the E44 you can switch both Digital I/Os to SPDIF or have one be SPDIF and the other AES. Remember that both the jumpers and switches must be altered to go from the default of AES to SPDIF. The format is set using SW200: Switch 1 controls Digital In/Out 1, while Switch 2 controls Digital In/Out 2 (E44 only). The OFF position selects AES format (default) and the ON position selects SPDIF format.
B) The default routing on the E22 delivers signals from the digital input to Record 3+4. On the E44 the default is that the digital inputs deliver signals to Record 5+6 for the first pair, and 7+8 for the second pair. In your DAW, make sure that the input selected corresponds to the desired signal source.
C) Make sure that the signal source is operating at the same sample rate as the card. Either the E22/E44 should be the clock master and the Digital signal source slaves to it, or vice versa, or both slave to a master clock. The E22/E44 clock source is set within the Lynx Mixer, the choices are:
* Internal - card is master
* External - slave to wordclock
* Header - slave to another Lynx card in system connected via the ICC clock cable
* Digital in - slave to device connected to the digital input(s)