Keith Floyd
Yes, the Keith Floyd! He was West’s cookery expert, popping up frequently on the mid-morning show; often enough for Venue magazine (November 1982) to remark that John Hayes should “not be distracted by [his] egotistical ramblings!” During the 1983 experiment with the “speech block”, Keith transformed into a shock jock, hosting a half-hour phone-in in which he vented his spleen on foreigners and anybody else who happened not to fit in with his view of the world. I don’t know whether the IBA intervened, but the phone-in (and Keith’s cookery slots) didn’t last long after that. It didn’t seem to affect his career very much.
The Guardian’s obituary (very comprehensive, and even mentions the phone-in)