https://community.usa.canon.com/t5/Speedlite-Flashes/Trouble-with-HSS-on-430-ex/m-p/18983#M1482 I have a 7d camera and 430 ex speed lite. On my last two shoots I had trouble in that my high speed sync would not stay activated after a while. It would shut itself off and the flash would not trigger as well as having the "H" disappear on the speed lite display panel even though I had not changed any settings on my flash or camera. I changed my batteries and that did not solve the problem. This problem did not occur until the last month. My flash is almost 2 years old. Any ideas on what is causing my problem? How do I have it checked out or would it still be considered under warranty if I could find my receipt? Fri, 29 Mar 2013 04:24:24 GMT Lsrwtr84 2013-03-29T04:24:24Z https://community.usa.canon.com/t5/Speedlite-Flashes/Trouble-with-HSS-on-430-ex/m-p/18983#M1482 I have a 7d camera and 430 ex speed lite. On my last two shoots I had trouble in that my high speed sync would not stay activated after a while. It would shut itself off and the flash would not trigger as well as having the "H" disappear on the speed lite display panel even though I had not changed any settings on my flash or camera. I changed my batteries and that did not solve the problem. This problem did not occur until the last month. My flash is almost 2 years old. Any ideas on what is causing my problem? How do I have it checked out or would it still be considered under warranty if I could find my receipt? Fri, 29 Mar 2013 04:24:24 GMT https://community.usa.canon.com/t5/Speedlite-Flashes/Trouble-with-HSS-on-430-ex/m-p/18983#M1482 Lsrwtr84 2013-03-29T04:24:24Z https://community.usa.canon.com/t5/Speedlite-Flashes/Trouble-with-HSS-on-430-ex/m-p/19287#M1483 <P>Hi Lsrwtr84,</P><P>&nbsp;</P><P>If you set a shutter speed on the camera that is within its normal sync speed range, high-speed sync is no longer active and you will not see the icon in the viewfinder.&nbsp; This is because high-speed sync is no longer necessary.&nbsp; This could very well explain why you are sometimes not seeing high-speed sync active anymore.</P><P>&nbsp;</P><P>If this is a time sensitive-matter, additional support options are available at <A href="http://www.usa.canon.com/cusa/consumer/standard_display/contact_us_consumer" target="_blank">Contact Us</A>.</P><P>&nbsp;</P><P>&nbsp;</P> Mon, 01 Apr 2013 14:02:55 GMT https://community.usa.canon.com/t5/Speedlite-Flashes/Trouble-with-HSS-on-430-ex/m-p/19287#M1483 Mykolas 2013-04-01T14:02:55Z