Unwanted guitar reverb

In the most recent updates of v4 my guitar sounds have changed. Every guitar sound, whether MS Basic or Gtr Vol 1, has now got long sustain making the parts awful to listen too. The ring-on continues for at least a bar for every note. No settings were changed but I now have the effect of aircraft hanger reverb. I have tried every visible toggle/setting to change the effect but it will not go away. Am I missing something please or is this a bug?

Gordon