Just received my xh -a1 back from canon ,for a micrphone repair.
Switched it on and I am not getting any sound either with built in mike or when using external mike, any suggestions.

Is the volume level set to manual, with the pots all the way down, by chance?

How do you know you're not getting any sound -- do you have the recording level display turned on? Headphone jack properly inserted? Headphone volume level up to midway? Or... is this is playback problem? More details, please...