[BioC] aCGH package error: MAD

[affy snp]

Hi list,

I am using aCGH package and run into an error like:

> hmm.merged(ex.acgh) <-mergeHmmStates(ex.acgh, model.use = 1, minDiff = .25)
> sd.samples(ex.acgh) <- computeSD.Samples(ex.acgh)
Warning: MAD could not had ben computed for one of the
samples

I searched the archive and did find any clue there. Maybe someone
could suggest how to cope with this?

Thanks a lot!

Allen