hi sinclairtv
this is quite a common fault on vestel chassis,caused by a glitchy eeprom, menu does cancel 'burn mode' but sometimes it constantly happens after the set has been swithed off/on, if they come back you will have to go into the service menu and turn burn mode function off, if the fault still happens a new eeprom is the only solution.
heres hoping you fixed it first time.
daz
ps. just rememdered! some time ago we were debating the use of a 24c64 eeprom in the samsung sets as aposed to the 24c256 , finaly got around to sticking one on the eeprom reader, chip was about two thirds full with all channels tuned in, so looks like there is plenty of room should they add extra channels after the full digital switch over..(and if theres not i supose we get the set back for another repair! (kerr ching)