ZMA controller reported C501 was issued a descent clearance; yet controller's display showed a climb...

Narrative:

Aircraft X checked on in level flight deviating for weather at FL340. Issued further deviation and gave a descent to cross obeys or 10 north of hurde at FL240. Aircraft Y was in level flight direct to sav at FL370. Shortly after the descent clearance was issued; conflict alert went off showing aircraft X climbing out of FL344 head on with aircraft Y. I questioned aircraft X on his altitude and descent clearance I had given him. He said that they were out of FL307 descending to FL240 but that we may show him out of FL283. I was slightly confused as to why he would say we would show him out of something differently. Over the past few weeks we have had several ads-B issues with aircraft showing on eram climbing or descending due to RA's without any actual issue or event. Neither aircraft had RA's and aircraft Y never said anything about the erroneous altitude error.I think we need to look into what's going on with eram and ads-B or these several aircraft instances. It really scared me to see him climbing; especially since he had just entered some moderate precipitation. At first I was concerned of turbulence but after pilot report it looked like a data error. These events have really startled a few controllers here especially with RA's happening.

Original NASA ASRS Text

Title: ZMA controller reported C501 was issued a descent clearance; yet Controller's display showed a climb which pilot report determined inaccurate. Controller stated several instances of this since ERAM and ADS-B.

Narrative: Aircraft X checked on in level flight deviating for weather at FL340. Issued further deviation and gave a descent to cross OBEYS or 10 North of HURDE at FL240. Aircraft Y was in level flight direct to SAV at FL370. Shortly after the descent clearance was issued; conflict alert went off showing Aircraft X climbing out of FL344 head on with Aircraft Y. I questioned Aircraft X on his altitude and descent clearance I had given him. He said that they were out of FL307 descending to FL240 but that we may show him out of FL283. I was slightly confused as to why he would say we would show him out of something differently. Over the past few weeks we have had several ADS-B issues with aircraft showing on ERAM climbing or descending due to RA's without any actual issue or event. Neither aircraft had RA's and Aircraft Y never said anything about the erroneous altitude error.I think we need to look into what's going on with ERAM and ADS-B or these several aircraft instances. It really scared me to see him climbing; especially since he had just entered some moderate precipitation. At first I was concerned of turbulence but after pilot report it looked like a data error. These events have really startled a few controllers here especially with RA's happening.

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	1543186
Time
Date	201805
Local Time Of Day	1801-2400
Place
Locale Reference	ZMA.ARTCC
State Reference	FL
Aircraft 1
Make Model Name	Citation I (C500)
Operating Under FAR Part	Part 91
Flight Phase	Descent
Flight Plan	IFR
Aircraft 2
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Enroute
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy

ZMA controller reported C501 was issued a descent clearance; yet controller's display showed a climb which pilot report determined inaccurate. Controller stated several instances of this since eram and ads-B.