Note that the return values are signed - so that represents -22
This is an undocumented error code - see:
wavecom.com/modules/movie/sc … documented
Also search the FAQ for “-22” and “ADL_AD_RET_ERROR” - it seems that this is not an uncommon problem 
I get the impression that there are a number of restrictions that need to be observed when using A&D storage, but which are not documented
eg, see:
wavecom.com/modules/movie/sc … .php?t=928
wavecom.com/modules/movie/sc … php?p=3332