.net - Timestamp being appended to image urls using ? instead of & -

for reason timestamp parameter keeps getting appended image url breaks urls in chrome due incorrect formatting.

example:

/media/1033/6199593743576161881eb.jpg?width=230&height=120&bgcolor=000000&mode=crop?timestamp=1373905702716 

in case it's relevant, umbraco v6 installation. result of background colour , mode not applied.

imageresizer not modify urls, nor aware of 'timestamp' parameter — else causing this!

it's apparent there either server-side logic/filtering making occur, or else javascript component modifying dom.

viewing html source should tell whether it's html filter or javascript snippet.

typically kind of behavior added 'debug mode' eliminate browser caching. i'd watch debug settings , see if modifying them solves problem. if so, please report here culprit.