BMW Pro Nav - Sat Nav arrow indicator / position issue

[p1tse]

I have a 2007 E61 with an original 2009 Sat nav disc
The problem I have is intermittent nav/ position issue. Either on Sat nav or just having the map up on the i drive showing position with the little arrow on the map, the arrow just goes off course, loses position at times.

Very frustrating when using the Nav and annoying when keeping an eye on local roads.

Previous owner said they had an issue and had it checked out but was all passed as fine and sorted with a new disc, however I still have an issue.

It works 60-70% of the time, but say even going down a known motorway the arrow could stray off the motorway on the map or worst just moves about on screen etc.

Anyone else with i drive and pro nav have had this issue?

[gizlaroc]

I had this on my 335i, I put a new GPS antenna in it from ebay for £6 and it was perfect after that.

I tucked the antenna under the dash behind the instrument cluster.

[eybic]

It does sound like a GPS issue as my TomTom does this when it doesn't have all the satellites in sight.

[p1tse]

gizlaroc said:

I had this on my 335i, I put a new GPS antenna in it from ebay for £6 and it was perfect after that.

I tucked the antenna under the dash behind the instrument cluster.

thanks.
I've only spotted a few other idrive pro nav owners have this issue.

any links to what GPS antenna I need and how do I hook it up?