As I was coming off the motorway this morning doing 65 ish my left indicator was blinking at almost double speed. At first I thought the rear bulb had blown but as it was darkish I could see in my mirrors that it hadn't.
Now here's the confusing bit. As I slowed down for the junction, so did the blinking. As I live in the country side & rarely see traffic on my way home I experimented with different speeds/rpm etc, and I worked out that low gear & high revs/hi speed sent the indicator into double time. It was only the left indicator as well, not the right.

Is this a reg/rec problem or indicator relay? I have aftermarket mini indicators on the back (they always seem to blow bulbs hence my original thought it was a blown bulb)