Ah yes, we regularly get undigested (unchewed, a-hem young lady!) peas, sweetcorn (I know, but she eats what we eat!), sometimes whole empty clementine segments, red/wholegrain rice, and seeds from grainy bread... ew! I always scrape it all off into the loo though and then rinse the nappies, can't bear the thought of putting poo in my washing machine
It definitely does seem to come and go, not sure why - hopefully the phase won't last more than a week or two and then you'll get a break!