For just about every sport I'd agree with you Cardfan, but IUPUI has a pretty strong recent history when it comes to volleyball. 5 of the last 7 seasons they've had 19+ wins, including an NCAA tournament appearance in 2013. This was also IUPUI's third straight win over the Cardinals.
I don't have an explanation as to what happened at IUPUI except they are always tough against Ball State. Don't let the Card's record fool you though. At Colorado State the Cards were trading punches against top 25 CSU and 16 Michigan and although they didn't get a W I think they showed they weren't backing down. Won the first set against both and then played tough in the losses. The Cards should use the experience down the stretch.