GA pilot reported being given a low altitude alert by ATC in the vicinity of dnn airport.

Narrative:

Upon approach to dnn; after having been cleared direct to the IAF for the RNAV rwy 32 by atlanta center; I was told to contact chattanooga approach. I contacted them; and was told I could not commence the approach due to VFR traffic beneath the undercast; and was given a radar vector north-bound and a frequency change. I misread the frequency and attempted to call them unsuccessfully; then changed the frequency and was told upon initial contact 'low altitude alert; climb immediately.' I was VMC above the clouds below; and have dual waas GPS units with current terrain databases. I knew my position; and although I had been vectored past the IAF; I was several miles south of the terrain. I asked for a westerly vector; and after an additional heading southwest bound; I realized I could descend VMC through the broken-scattered clouds and asked permission to cancel. The controller replied 'that would be best for both of us.' I squawked 1200; and descended beneath the layer; and completed a successful visual approach.although I was on an IFR clearance; I was in VMC conditions the entire flight. The repeated vectoring around the IAF caused me to need to re-load the approach three times; which is challenging in single-pilot operations. I never felt unaware of my position or the position of the terrain. However; the verbal instructions from the approach controller and his tone of voice made me decide to file this report.

Original NASA ASRS Text

Title: GA pilot reported being given a low altitude alert by ATC in the vicinity of DNN airport.

Narrative: Upon approach to DNN; after having been cleared direct to the IAF for the RNAV Rwy 32 by Atlanta Center; I was told to contact Chattanooga Approach. I contacted them; and was told I could not commence the approach due to VFR traffic beneath the undercast; and was given a radar vector north-bound and a frequency change. I misread the frequency and attempted to call them unsuccessfully; then changed the frequency and was told upon initial contact 'low altitude alert; climb immediately.' I was VMC above the clouds below; and have dual WAAS GPS units with current terrain databases. I knew my position; and although I had been vectored past the IAF; I was several miles south of the terrain. I asked for a westerly vector; and after an additional heading southwest bound; I realized I could descend VMC through the broken-scattered clouds and asked permission to cancel. The controller replied 'that would be best for both of us.' I squawked 1200; and descended beneath the layer; and completed a successful visual approach.Although I was on an IFR clearance; I was in VMC conditions the entire flight. The repeated vectoring around the IAF caused me to need to re-load the approach three times; which is challenging in single-pilot operations. I never felt unaware of my position or the position of the terrain. However; the verbal instructions from the Approach Controller and his tone of voice made me decide to file this report.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1648187
Time
Date	201905
Local Time Of Day	0601-1200
Place
Locale Reference	DNN.Airport
State Reference	GA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	Descent
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Flight Engineer Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 1200 Flight Crew Total 25000 Flight Crew Type 250
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance Inflight Event / Encounter CFTT / CFIT
Miss Distance	Horizontal 5 Vertical 1000