"InterCheck[…] thread […] caught burning CPU!"

Twice my MacBook Air running ox x 10.9.2 and Sophos home edition 9.0.8 has gone unresponsive with a beachball, requiring restart, with the following in the logs:

    "InterCheck[32673] thread 516075 caught burning CPU! "

and

    "InterCheck[32673] caught causing excessive wakeups"

Here's these lines in context:

Apr 7 11:14:20 haywire.local com.sophos.intercheck[32673]: Info: On-access scanner started at 11:14 on 07 April 2014
Apr 7 11:44:49 haywire kernel[0]: process InterCheck[32673] thread 516075 caught burning CPU! It used more than 50% CPU (Actual recent usage: 80%) over 180 seconds. thread lifetime cpu usage 91.382063 seconds, (89.651012 user, 1.731051 system) ledger info: balance: 90008073040 credit: 91368350374 debit: 1360277334 limit: 90000000000 (50%) period: 180000000000 time since last refill (ns): 112342164928
Apr 7 11:45:16 haywire kernel[0]: process InterCheck[32673] caught causing excessive wakeups. Observed wakeups rate (per sec): 824; Maximum permitted wakeups rate (per sec): 150; Observation period: 300 seconds; Task lifetime number of wakeups: 47330

I'm blaming InterCheck for the hanging, because they were the last log entries before the restart was required. Can someone tell me what these log entries mean, if this is a known problem, and a possible way to avoid this situation?

Thanks!