Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Inteliquent (IQNT) plunged as much as 28% during intraday trading Thursday after the network interconnection specialist announced preliminary earnings, and postponed its conference call as a result of an ongoing investigation by the audit committee of its board of directors.

So what: During the second quarter, Inteliquent says its voice revenue fell 2% year over year, to $49.8 million, missing analysts' average estimates, which called for sales of approximately $54.3 million. Meanwhile, adjusted earnings fell 12% from the same year-ago period, to $16.3 million, and income from continuing operations more than tripled to $35.2 million, primarily the result of a $24-million gain on the previously announced sale of part of Inteliquent's global data business.

The biggest shock, however, came as Inteliquent said its earnings conference call will be postponed after its board determined an internal investigation should be performed regarding whether two figures were overstated in its most recent Annual Report, including a $75.3 million impairment charge, and a net loss of $78.1 million for the year-ended December 31, 2012. 

Now what: Unsurprisingly, at least one law firm has already come out of the woodwork to announce potential securities claims against Inteliquent, and even after today's drop, it's worth noting that shares of Inteliquent are still up nearly 150% so far in 2013. As a result, its hard to blame investors for taking some money off the table given today's uncertainty.